, if I am a simulation that is not aware of the fact, I must be able to act and react in my world. In that case, I am not a simulation of anything. — Ludwig V

We seem to be unable to communicate. A simulated thing that was causally disconnected from its environment would be an inaccurate simulation, unless perhaps it was a simulation of dark matter, which really is unable to 'act and react' in its world in any way beyond contributing to the curvature of spacetime.

I can think of models of the weather system that are used to predict the weather. They can be called simulations. They remain quite distinct from the actual weather. There are neither storms, nor rain, nor sunshine inside the computer.

But there very much is storms and rain in the world simulated. It wouldn't be a weather simulation without such things.
Similarly, a simulation of a conscious being would not make a computer conscious, but that doesn't mean that simulated person is not conscious. Bostrom suggests that is exactly what's going on.

Yet the point of the exercise is that it remain as close as possible to what actually happens/-ed. (I can't imagine what the point of ancestral simulations would be, if not that.)

I suppose that's the point, but Bostrom has zero awareness of chaos theory if he thinks that will happen. And he doesn't suggest it. He makes no suggestion that us (the simulation) is evolving in any way the same history as in the simulating world. But yes, what's the point of running such a simulation? Not for prediction purposes, and that's almost always the motivation behind running any simulation.

Once you suppose that the simulations are conscious

I don't think anybody is supposing that. See the above. Yes, a simulated person would behave differently than 'their originals', which I put in quotes because there are no originals in the scenario in question, except as a wild guess at an initial state, giving some characters the same names and roles as historic figures.

The point of the simulations would be lost if real people capable in their own right of acting and reacting in their world.

That sentence lacks a verb, and you lost me. Real people are the ones supposedly running the simulation. The 'point of the simulation' is meaningful to those that are running it. The simulated people have no access to those running the sim, and if they detect or just suspect that they are a sim, they can only guess at the motivations behind the running of it.
Your wording in the verb-less sentence suggests that simulated people would perhaps need to exert some sort of free will over the physics of the simulation. That model isn't compatible with Bostrom's view.

It's me trying to EXPLAIN that OTHER people are using the same word for two very different things. — fishfry

Or its the other people always meaning the same thing, and thus needing only one word for it.
You seem to be the one finding two different meanings, one which sounds like how others use 'simulation', and then this other thing which for reasons not spelled out, require exactness, and is perhaps not computational. I have no idea how to simulate something non-computational, let alone doing it exactly. I don't think anybody else is suggesting any such thing.

But I also maintain that the hypothesis is false. So there's no contradiction.

Well yea, you deny the premise that physics is computational at the necessary levels of precision needed.

So I am not in a position to dictated whether or not 2 + 2 = 5 because I hold that the proposition is false?

No, you're not in the position to say what other people think follows from accepting that 2+2=5.

Pacman ONLY involves computation.

You said "Then whatever [VR] is doing is not computational.", and now you say it is nothing but.
Perhaps you don't consider pacman to be an example of VR. It's admittedly crude and not deeply emersive, but most action video games are nevertheless a form of VR.

The point seems moot. The subject of the topic is simulation theory, not VR theory. VR examples have little to no bearing on simulation hypothesis, a hypothesis you just plain deny due to your lack of belief that a human is computational.

The points you're making in this post are trivial and wrong, not up to your usual standards.
— noAxioms

I don't think I ever said that. This quote is mistakenly attributed to me. Maybe I'm wrong about that. It's a long thread.

I take your point about real time computing, but that does not change the definition of computability.

You seem to go on endlessly about me somehow disagreeing with the definition of computability. I'm not. Real-time issues don't exist in simulation hypothesis, so those are moot until one starts talking about something other than SH.

So who is the me that's being simulated?

Under the simulation hypothesis, you are yourself, which is tautologically true, SH or not. There is not a different 'more real' or 'less real' fishfry somewhere else. It is an ancestor simulation, not a simulation of a fishfry model. Your maker is still your mother, also part of the simulation.

You (or you quoting Bostrom) say that I'm a simulation

You are part of one large simulation, and yes, me quoting Bostrom. I don't buy the hypothesis for a moment.

I'm asking what I'm an approximation of.

You are not an approximation of anything. The simulation is an approximation of the physics of a system (a planet perhaps). You are part of the state of that simulation.

So do I correspond to an actual person or not?

Probably not, unless the simulation's initial state was very recent (our time) and that initial state included a real person who happened to identify as fishfry. I seriously doubt the GS people centuries in the future would know almost anything about you except your parental lineage, all of which is only relevant if the initial state was set since your birth. It has to start somewhere, and that means that the people of that time are created in thin air, with memories totally consistent with their nonexistent past. Doing that requires a full knowledge of how memory and consciousness works, not just a model of how physics works. The initial state requires far more work than does the simulation itself, which is fairly trivial if you get the state right.
Such things are easy with weather and car crashes, but a nightmare for something complex.

As I go through my daily life and encounter other humanoid-appearing creatures, is there a way for me to determine which correspond to actual people and which don't?

Probably none of them, unless they are older than the date of the initial state. Anybody conceived after simulation start has zero probability of having a corresponding real person.

Are the non-corresponding creatures like NPCs in video games?

No. They're no different, except they have real memories, not fake ones put there by the initial state. Maybe the sim only last 10 minutes and everybody is 'corresponding'. This is presuming that the people of the future know exactly who and where everybody is at some random time centuries prior. They don't.
Why do you harp on this? Of what possible importance would it be to anybody in a sim to have a corresponding person (long dead) in the GS? I do realize that I am asking this question of a person who thinks people are special in the universe can cannot be computational like everything else.

You know you are really out on a limb here

Bostrom is maybe. You forget who's pushing the hypothesis. It isn't me, but I'm a computer person and at least I understand it enough to see it for the nonsense it is.

but only because my vat programmers have erased my memory.

SH is not a BiV scenario. VR is, but Bostrom is not talking VR.

So we're all non-corresponding players now? Not just some of us?

An corresponding people from the initial state of the sim would correspond to people centuries dead in the GS world, so nobody can correspond to any living 'real' person.

Simulation as approximation. As opposed to simulation as instantiation.

Sorry, but despite your repeated use of that word, I don't know what you mean by it. You've mentioned that it needs to be 'exact', and the exact physics of even a small trivial real system cannot be exactly simulated, so there cannot be what you call an instantiation. So we're back only to simulations of the approximate physics of some chosen system.

This ignores the possibility that there may not be "lots of civilizations". — Janus

Bostrom addresses that point in his first of three possibilities listed in his abstract.

I didn't get a notification of this. Glitch the matrix? — Patterner

I occasionally get a reply that doesn't make it to the 'mentions' list. Maybe a glitch. I suspect it perhaps might be a post that was already posted, and then later gets edited to mention you, but the one in question here is short and a reply only to you, so that's a significant data point against my theory.

My problem is that I don't understand what metaphysics is, — Ludwig V

I can answer this. Metaphysics is about what physically is, and physics is about what physically is measured. That's a crude definition, but what it comes down to is that the phrases 'physically possible' and 'metaphysically possible' mean the same thing. You can't have one without the other. Metaphysically possible means that there exists a metaphysical interpretation where the thing in question is physically possible.
So for instance, physical determinism is a metaphysical issue. There are some valid interpretations that are deterministic, and some valid interpretations that are not. Therefore determinism is metaphysically possible, and therefore determinism is physically possible.

Everybody posting seems to treat 'metaphysically possible' as some weird sort of realm between physically and logically possible, resulting in confusion when nobody can come up with an example of something distinct.
So any argument against the lamp, or recitation of numbers, becomes a logical argument because these arguments have no application to physics. They are all metaphysically impossible for the very reason that they are physically impossible.

Supertasks play on the difference between the physically possible and the logically possible to create an illusion.

This seems to say it. It is a logical issue, but with applications to the physical when the scenario in question doesn't involve physical impossibilities.

After completing the supertask the lamp must be either on or off — Michael

I am willing to accept this statement, but you are not willing to engage with any of the faults identified with your logic. Hence I can only presume you have no counters to them, resorting only to changing the subject every time a fallacy is pointed out. I for the most part have dropped out due to this lack of engagement.

It is impossible to complete any action an infinite number of times. — Ludwig V

This is Zeno's strategy. Just beg your conclusion.

The notation does not define an end, — Ludwig V

There it is. Not possible due to the asserted necessity of a bound of something which by definition has no bound. All the arguments against seem to take this form. Even Zeno avoided this fallacy, and his argument was made before the mathematics of infinite sets was formalized.

Your post seems to add nothing new, and does not appear to engage with any of the points I've made. I have nothing to add till I see a need to write something I haven't already said. — fishfry

Myself as well. I have dropped out some time ago, and not surprisingly, nothing new has been posted. But I did chime in to define 'metaphysically possible' since the term seemed to be used in a way in which it was somehow meaning something different than physically possible, which it cannot be.

But that would mean that the simulation is a reality of its own, independently of the "real" reality. — Ludwig V

I want to agree and disagree with this. By most definitions of 'reality', yes, a simulated world would be a reality of its own, but it being called a simulation is an explicit admission of it being dependent on the deeper reality running the simulation, just like saying 'God created the universe' makes the explicit relation of the universe being dependent on the god. Neither case is that of a 'universe on its own'.

Well yes, by my definitions "couldn't simulate exactly" is synonymous with couldn't simulate.

Again, we have this ongoing equivocation of the word simulation. I agree with you that when I program my computer to simulate gravity or the weather, the simulation is not exact. It's an approximation. — fishfry

The above two comments seem to contradict each other. By your definition, a simulation isn't one unless it is exact, and then you give examples of simulations that are not exact.

But when the GS simulates my consciousness and the experience of my senses, that is exact.

You also said that consciousness is not computational, and therefore the GS cannot simulate via computation, a conscious thing. That puts you into a position to not dictate whether or not those holding a different opinion would say that exactness is required or not.

Then whatever [VR] is doing is not computational.
...
If that is true, then VR is not computational.

So pacman does not involve computation. Hmm....

If you execute Euclid's algorithm faster, it is still Euclid's algorithm and has no capabilities (other than working faster) than it did before. It does not acquire more side effects or epiphenomena or "emergences" like consciousness or realism.

Agree, but I was talking about VR when I said that the rate of computation is essential. None of your examples above are VR examples.

Other examples is any other kind of real-time programming such as a self driving car. A car cannot function if its processing uses paper and pencil. A certain minimal rate of computation is required, or the task cannot be done. Computing slowly isn't enough if you take 3 months to see the stop sign. You seem to assert that what a self-driving car does therefore cannot be computation, but it very much is.

What does running an algorithm fast do that running the same algorithm slowly doesn't?

I already told you: It gets it done before the computer ceases computing. A human with a pencil lives maybe 50 years (with the pencil) and accomplishes what a computer can do in under a second, and computers tend to last longer than a second before they fail. A computer can come up with an answer while the answer is still needed. In a simulation, there are no deadlines to meet (except getting something done before the computer fails), but in any kind of real-time programming, it must be completed before the output is needed by the consumer of that output.

Even if I agree 100%, the definition of computability specifically ignores matters of time, space, energy, and resources

Ok you agree. That's good. So if I write some code, and when I run it slowly it computes Euclid's algorithm; and when I run it fast, it computes Euclid's algorithm and whistles Dixie; then by the definition of computability, which you have now agreed to, whistling Dixie is not a computable function. It it were, the slow algorithm would get the same output as the fast one.

If it whistles Dixie, it is computing something different. Both should have identical output. Euclid's algorithm isn't a real-time task.

That's the only point I'm making. But it's important, because you claim that running the algorithm fast makes a qualitative difference.

Only to a real-time task, and none of your examples are one.
.

Wait. There's an abstract mathematical model of a human and any particular sim is only an approximate instance?

There's a model of physics, and any sim is only a computable approximation of that. Bostrom says that a human is a product of physics, and thus can be functionally simulated given a sufficient level of detail, which is still classical.

That's more like Tegmark, that we're all mathematical structures.

Same model, different supervenience, if I get my terminology straight.

So there's a simulation of a person AND there's a real person being simulated?

I don't know what you think it means for a real person to be simulated. Bostrom suggests a sim of ancestral history, which means that random new people get born, and these people do not in any way correspond to actual people that might have existed in the history of the GS. Much depends on what period of history they choose for their initial state.

Now you have TWO mysteries instead of one. I'm a simulation and there's a real me above that? I don't believe that.

That would be something other than 'ancestral history'. You say take a molecular scan of a real person, create a sim model of that exact arrangement of matter, put it in a small environment, and see what it does. That's far more likely than this 'ancestral' thing, but it also would be trivial for the simulated person to realize he's not the original since he's been put in this tiny bounded space, a sort of jail, when he remembers getting into the scanning machine.

Now according to your stated beliefs, that simulation wouldn't work. It is computational and you say a person isn't, so the simulated thing would not be functional at any level of detail.

Then you tell me that I'm only an approximation of a real person.

No, I did not suggest there needs to be a 2nd fishfry that is 'real'. Ancestral history simulations certainly don't produce simulated people that correspond to people in the GS world.

I no longer accept the coherence of the thesis being proposed. I'm a sim fishfry and there's a "real" entity fishfry who's being simulated, but who isn't reall there.

No, not two of you. Bostrom's sim hypothesis would have all of us being in one large simulation, and no real fishfry in the GS world. I apologize if something I posted led you to conclude that I was suggesting otherwise.
What is approximated is the physics. I can simulate planetary motion by modeling Earth as a point mass. That's a super-trivial approximation of Earth that works for seeing where it is 100 years from now, but it needs more detail if you say want to see which way the planet is facing in 100 years.

What we do is invent video games that use different physics and are nothing like us at all.

Yes, but over time, many video games keep getting closer and closer to the sort of reality we'
re used to. Not all of them. Some are still total fiction with deliberate fiction physics, if they have physics at all. They're also video games, which makes them VR, not simulations.

I've seen videos where someone debunks every other relativity video on the Internet

It's low hanging fruit to debunk various videos. There is indeed whole sites dedicated to debunking relativity in all possible ways, and it is a interesting exercise to find the fallacious reasoning in every one of the arguments. And I do know enough physics to do it to almost all of them.
The delayed choice quantum eraser isn't really an experiment having anything to do with relativity theory.

That's the astonishing thing. It plays pretty well even then, in games whose length exceeds the length of any of its training data..

News to me as well. It seems to require at least some level of what would qualify as 'understanding'.

Why are almost all my quotes labeled "keystone"?

[The GS] can't be simulating itself, you just agreed with that. — fishfry

I said it couldn't simulate itself exactly. I didn't say it couldn't simulate itself.

Faster does not help when it comes to computation.

It is necessary for a VR, but not a simulation, all of which is pointed out in my topic. It's why a sim can be done with pencil/paper and a VR cannot. Still, Bostrom needs a fast computer because a simulation with paper and such would have humanity go extinct before a fraction of a second was simulated. Bostrom is not making an 'in principle' argument.

Going faster can never let you compute more things than you could with pencil and paper. If going faster makes a difference, then the difference is not computational. It's something else.

True only in principle. In reality, each number written on a paper will likely rot away before it is needed for the next step. The guy with the pencil will die, as will all of humanity. So will the superfast computer (it cannot run forever in practice), but it will have gotten a lot further than the pencil team, and a lot further than any TM, however pimped out you make it.

That's a different kind of computability: the ability to get it done before the demise of the thing doing the computing.

You agree with me on this point then, am I correct?

I agree with all your points on the definition of computability, but I wasn't talking about that.

This was about whether my mind somehow extends to Ms. Pac-Man's. I think it's an important point, not just semantics.

OK. I seem to be blowing it off to semantics, and I made MsPM an extension of me, not an extension of my mind. I consider myself to be conscious, not just a body that contains something that is.

It's a thousand percent different. It's apples and rutabagas. A simulation of gravity is the execution of an approximate mathematical model.

Bostrom's view is that a sim of a person is also the execution of an approximate mathematical model. That this conflicts with your opinion means that your opinion is incompatible with what Bostrom hypothesizes.

The GS's simulation of us is exact. We ARE the simulation. This seems to be a real point of difference, not just semantics.

If you mean that the thing simualted (us) is exactly the same as us, that is tautologically true, yes. But I'm saying that the simulated 'us' cannot be an exact simulation of a person in the GS world.

Then what is the thing being simulated?

Yet again, the thing being simulated is 'ancestral history', whatever that means.

You mean there's a real me

Bostrom does not suggest that there is or ever was a real fishfry in the GS world. You are part of the simulation, and that's it. The history being simulated is quite different than the one that actually happened way in the past history of the GS world, although the initial state of the simulation presumably had similarities to some actual past state of the GS history. Bostrom gives no indication of when this initial state was likely placed. Last Tuesday? A minute ago? 50000 years ago when humanity just started looking like us?

You are misconstruing what Bostrom and other simulationists believe, then. They're not saying we're an approximation. They're saying our exact reality is being instantiated by a computer.

Again, tautologically true. But our reality is the causal result of an approximation of some past GS state.

Why would anyone run an ancestor simulation? We don't, why should our future selves?

Apparently 'because they can' and we don't because we can't. But visionaries have always had a lot of trouble guessing what purposes would be served by future high computing capacity. Anyway, I don't buy that reasoning because it's only there because the hypothesis needs it to hold any water.

I've learned a lot about MOND and dark matter from her.

And she exquisitely tore apart a lot of the woo surrounding the delayed choice quantum eraser since that experiment is so often billed as an example of reverse causality. The one I tore apart had to do with general relativity, which I don't even know that well, but I know enough to show the assertions in the video to be bunk.

I have just been made aware, via flannel jesus, that an LLM has learned to play chess by training on nothing more than the records of games in standard chess notation.

That works great for opening, perhaps for 20 moves even. But eventually it has to get to a position that it hasn't seen in its training data, and then what? It can't just auto-complete with more text, since the text given would likely not be a legal move. So I'd like to see an article about how it proceeds from a middle-game. Turns out that the LLM is often more capable than I give it credit for. Scary.

Sim theory doesn't say the simulator approximates our world. Sim theory says the simulator creates or instantiates our world. Exactly. — fishfry

An exact simulation of any GS world cannot be done by that GS.
My comment to which you replied talks about us being the GS, and when we run a simulation of this world it is always an approximation. My example was a VR one, but it goes for an actual sim as well.
If our world is a simulation, then it is either a total fiction created by some completely different (and more capable) GS world, or, per Bostrom, it is an approximation of the GS world. It cannot be exact for several reasons, another of which is that our world is not finite in extent.
Anyway, read Bostrom. The paper sets out details of where the simulation goes into greater detail (but still an approximation) and where it approximates to a greater degree.

If the simulator is only approximating our world, then what is the real world?

The base simulator IS the real world, and it isn't approximating our world, it is approximating its own world according to Bostrom. I say 'base' because we might be 13 levels down or something, but it cannot be infinite regress.

Do you think (or does anyone think) the dots in Life have an interior monologue?

Not me. There's probably somebody out there that does. It's like asking if electrons have an interior life. Wrong question.

Bostrom asks, "Are you a COMPUTER simulation?" (my emphasis)

If he meant computer as understood by some future society but not by us, he would have said that. He didn't. Did he?

I suspect he meant a computer as we know it today, but oodles smaller/faster, as if Moore's law can continue for many more centuries. The computers of today are pretty inconceivable to those that first made them, as are the applications to which they can be applied.

You agree with me on this point then, am I correct?

Being correct is not a function of finding one person that agrees with you on something. We could both be wrong.

Can you remind me of what we're agreeing or disagreeing on then?

Well for one, that mind is computational or not.

My only concerns with what you've said so far are:

1) That simulation theory claims the simulator approximates some deeper reality; and

2) That Ms. Pac-Man is an extension of my mind and can be said to have an inner life, namely mine.

About point 1: It has been proven that a world like ours cannot simulate itself perfectly, so it has to be limited, an approximation at best.
About 2, the difference is pure language. You use words differently than do I. I see no fundamental differences between our views.

I hope that we are agreed that a simulation of gravity or a simulation of the stock market is not the same use of the word as the GS simulating my mind for me.

I don't see a different usage of the word, no. But again, this might just be a difference in language, how each of us uses the words in question.

The latter is a complete instantiation, not just an approximation.

Again, that cannot be. That's not possible. All of them have to be approximations.

Any simulation of something 'real' must be.

Nonsense. Real things are simulated all the time, and all of them are approximations.

The physics of the simulation will be different than the physics of the GS.

Correct. It needs to be close enough to achieve the goal of the simulation, but it doesn't need to be closer than that.

You are misconstruing what Bostrom and other simulationists believe, then. They're not saying we're an approximation. They're saying our exact reality is being instantiated by a computer.

He goes into some detail about what parts are more heavily approximated and which are done to greater detail.

Ok. But why would they do that?

Indeed, why? I see no reason to do it, even if we had this unimaginable capability.

A person does not suddenly become disreputable by virtue of being filmed.

Agree. I said I didn't get my physics from videos. I didn't say that anybody that appears in a video is disreputable.
I did take apart a Sabine video, showing it to be flat out wrong. It shows that the videos are not peer reviewed, and a good physics source is. This doesn't make Sabine disreputable. It means mistakes remain where peer review is absent.

My consciousness is the thing that has the experience, and science has absolutely no explanation for that.

You have no more explanation than science does. Just saying that your comment, true or false, isn't evidence one way or the other.

Wait, you just got through emphasizing that functional behavior is understanding. If an LLM passes the bar exam, by your definition it understands the law. But now you are going back on that.

Fair enough. I hold the bar higher for LLM because you can ask it to write a program to do a small thing, and it does, but it fails for something more involved, any task that requires more understanding of a deeper problem. This is why no LLM is replacing human programmers at corporations (yet), even if they very much are writing papers for students.

Bottom line is, the LLM algorithm isn't "understand, then write about that understanding", it is more "write something likely to be a plausible reply", a reworded plagiarism of pre-existing content.

If you agree with me that a TM is not a person, why are we having this conversation?

Because asserting that a TM is or is not a person is very different than asserting that a TM and a human are or are not capable of simulating each other.

I hope that people here have heard about the Elitzur–Vaidman bomb tester — Linkey

Having heard of it and understanding it are two very different things,.

The bombs in the referenced experiment are never in superposition of anything. They're real classical bombs, some of which are functional and some of which are duds, with the only way to tell is to look at them, except any light at all triggers the bombs that aren't duds.

The procedure to detect some good bombs does not involve putting any of the bombs into a state of superposition, something not really possible with a complex classical object, let alone an entire planet. But the bomb-detector test is something you can actually build in a lab, albeit an incredibly dark one.

I did object to your idea of approximation. My understanding is that simulation theory creates reality, it does not approximate it. — fishfry

If I try to simulate our actual world, I must approximate it since perfect simulation is impossible, requiring, among other things, infinite precision variables. So Lara Croft has, among other traits, square legs. All very crude. It gets better in later years, but still an approximation of what it wants to be.

If I simulate Conway's game of life (not our actual world, but one with very simple rules), well, it necessarily would have bounds, but otherwise would not be done as an approximation.

and operates via the laws of computation as we understand them.

No, operates under the laws of computation as they (in the far future) understand them. Not under our current understanding.

It's just a magical speculation at this point.

Agree with that. Hence my aversion to magic.

The exact same people who disdain God love the Great Simulator. I find that viewpoint lacking in self-awareness.

I agree with this. I'm certainly not promoting sim theory.

I hope that we are agreed that a simulation of gravity or a simulation of the stock market is not the same use of the word as the GS simulating my mind for me. The latter is a complete instantiation, not just an approximation.

Both will always be an approximation. Any simulation of something 'real' must be. The physics of the simulation will be different than the physics of the GS. If the two are close enough, then the simulation can achieve its goals. Hence weather forecasting not being a total waste of time.

This was the first of many links I found. It's commonly done. Simulation to predict sporting events is done all the time.

That's fine, but none of those has actually produced a real game before it was played. Sure, it can be used to set odds. Sure, it gets the final score right sometimes, but never the way the score gets that way. Of course the stock market is similar, but one can simulate the effect of certain news on the market. It can simulate a panic, and help test methods to control such instabilities.

You have a subjective experience of your mind. Any theory of mind has to explain it or hold it as a mystery.

Don't need a theory. Just a simulator. If it works, I don't have to know how it works. If it can't work, then it wont.

Bostrom says that we are a simulation. And the question is, of what?

"of ancestral history". His words. A fictional one at best, just like the football simulator. It's not going to show any historical events we know unless you start the sim just before they happen. If they start the simulation far enough back, there won't even be humans in it, ever.

Smoot did a TED talk. I get all my physics from Youtube these days.

Yea, I saw those links. I didn't watch the talk, because I don't get my physics from there.
I still have no idea what Smoot is proposing.

Well, I agree that if mind is physical but not computational, a new definition of computation must be in our future somewhere.

Bostrom thinks mind is computational. I see few detractors that claim that it cannot be, and thus he must be wrong.

The funny thing is that, other than civil war re-enactors. WE don't do ancestor simulations.

I'm not sure if LARPing qualifies as a simulation. They all know it's an act. Nobody really wants to kill the opposing side.
It happens a lot by me since I'm in a USA town that regularly holds a celebration of the British destruction of the place. The LARP types (reenactors) love it because the red-coats hardly ever get to be the guys that win. The blue guys fire back, but lose, but in reality there was no resistance. Everybody skedaddled and the place was burned down.

My body processes the nutrients in the ice cream. My consciousness experiences the enjoyment.

So the consciousness is a separate thing, not just a different process of the body that utilizes different noncomputational physics. If the latter were true, then the body would be liking the ice cream, just via a noncomputational mechanism.

Even if pleasure is a chemical response in the brain, my experience is the pleasure. The chemicals in the brain don't have experiences, I do.

Funny, but I totally agree with that wording.

The chess pieces don't enjoy playing the game,

Only because you choose not to consider them to be part of you, just like when you say "Also my body". That's a choice to include that.

I say the system understands nothing, any more than the computer running a chess program understands chess.

I would say that a thing with no understanding of chess would not be able to win the game. Again, the different in our views seems to be a language one. Two systems (black boxes) are doing the same thing, but the word 'understands' only applies if it's done the magic way and not the computational way. I take a more pragmatic definition: If it wins or even plays a plausible game, the word 'understands' is functionally applicable.

An LLM passed the bar exam. That's impressive.

It would probably slaughter any human at Jeopardy or some other typical trivial game. But I agree, the word 'understands' is pretty inapplicable to the LLM.

There are no structures in the brain that implement Turing machines. The neurons don't work that way.

If you mean that a brain isn't implemented as a Turing machine, I agree, but neither is any computer anywhere. The circuits don't work that way.
Also, a brain is just part of a person-system just like a CPU is part of a self-driving car.. A person is conscious, not a brain,

As a Turing machine or a digital computer?

A person is neither. It can in theory be simulated by either of those, but it wouldn't be done by modeling the person as either of those. A person is no more a Turing machine than is the weather. A digital computer is a Von Neumann machine, and a person isn't one of those either. There are digital circuits involved however. Wires, on/off states, etc. No clock. No bus. No instructions.

Place the mirror flat on the floor like a rug — Agree-to-Disagree

It's... still not flipped vertically. — Lionino

Yea, A2D, what were you thinking? It's goes on the ceiling, duh! Putting on the floor requires you to step on it and break it.

To flip something vertically means to draw a horizontal line in the center, and take everything in coordinate +1 and put it in -1, +2 to -2, and so on, now take -1 and put it in +1, -2 to +2, and so on. — Lionino

How does putting the mirror on the floor not do exactly that (assuming x axis is vertical, usually it is y or z by convention).

A concave mirror (on the wall, sufficiently distant) rotates the image 180 degrees, and still flips it front to back, not top to bottom.

Oh ok these definitions are changing.

Simulation, in the sense of simulation theory, means that my reality (VR) or my very self (Simulation) are exactly being created by the Great Simulator (GS from now on). — fishfry

I put out some definitions in my topic
Simulation theory and VR theory are very different, but you seem to be using simulation for both. I often shorten the former to 'sim'. I am OK with defining GS as the world running the sim or the VR. With VR, you are in the GS world (but not necessarily of it), and with sim you are not.

If the GS is only approximating me or my reality, what is being approximated?

Depends on if its a sim or a VR. My topic covers this.

The word simulation is always accompanied by "of." If there is a simulation, it's a simulation "of" something.

Well, in sim theory, it is a simulation of at least me, so I disagree with your assertion that there is no 'of' there. In VR theory, it is the creation of my artificial experience.

So when I say that intelligence, or mind, or the world, is physical but not computational, I mean that the universe does something that is physical -- involves the atoms and the quarks and the quantum fields and whatever future physics will be discovered -- that transcends our current understanding of computation.

Fine. You don't buy into the possibility of simulation theory since it contradicts other values which you hold to be true.
You say there might be 'future physics' discovered that completes your model, but the GS might already have that understanding, and might have built their sim in such a way as to leverage it.

Ok, but that's not how the TED talkers would see [difference between ID and sim]. They'd mock intelligent design, yet believe in simulation.

Besides the ridicule fallacy, how does that differ from the way I see it?

I hope that we are agreed that a simulation of gravity or a simulation of the stock market is not the same use of the word as the GS simulating my mind for me. The latter is a complete instantiation, not just an approximation.

Well, you deny the possibility of the latter, but I find it to still be the same use of the world. A simulation of our physics is necessarily an approximation since there is no way to represent anything physical exactly, so for instance it is probably going to be discreet physics with a preferred frame of reference.

Are you equivocating the word simulation? Simulation theory does not mean the same as when we simulate the Super Bowl to predict the winner.

How would anybody go about doing that?

The GS instantiates my mind and/or my experience.

In sim theory, there is no 'my mind' to instantiate. It is not necessarily a simulation of something that also exists in the GS world. Most simulations are of nonexistent things. I suppose the weather is an exception to this since the initial state is taken from the GS world, not as a work of intentional design.

Apologies if I confused your views with Bostrom's.

Good, because I think Bostrom's hypothesis falls flat.

A thing can't simulate itself.

That's well known. Godel showed it for instance.
I mean, they can, but at far slower efficiency. I wrote a program that essentially simulated itself for profiling purposes. You could simulate the execution of any code (including itself), but it ran at about a 1/10000th of the normal speed, and optimized that to about 1/40th the normal speed. That could simulate itself, but per Godel, it could not be used to see if it finishes.

I always want to ask the simulation proponents, simulation of what?

Bostrom is clear on this. It is a simulation of ancestral history. I mock that suggestion in my topic.

I had a funny thought. Just as all waves must travel in a medium; yet light is a wave that does not require a medium; perhaps the GS simulates without the need for an "of" to simulate.

I can't see a simulation not having a model to run. There's always an 'of', else the task is undefined. So I could run a simulation of a three legged creature to see which kinds of gaits it might find natural. There is no creature in the GS matching the one being simulated, but there's still an 'of'.

We agree then. Neil deGrasse Tyson and George Smoot believe in simulation theory.

Tyson just seems to ride on Bostrom's paper ("<-- what he said"), which I doubt he understands.
Smoot knows what he's talking about at least, but I could not find a paper/article with his hypothesis to get even a glimmer of what he's suggesting or what evidence he claims supports it. Perhaps something concerning the CMB. It's all you-tube, and I don't get my physics from you tube.

My understanding is that simulation theory claims it's all a computation.

Bostrom suggests that. A different sim theory might not. We know nothing of the GS, so I agree, it differs little from deism. Bostrom says we know everything about GS world since they us in 'the future'.

But any function that a quantum computer can compute can already be computed by a classical computer. And the proof is that quantum computers are often simulated on classical hardware. They run slowly, but in principle they do the same things either way.

Agree

And simulation theory is God restricted to our current notions of computation.

It is only this constricted if one presumes the GS world has the same constraints as the world we know.

But why should the GS run ancestor simulations? Isn't it rather arrogant of us to impute motives to the GS as if the GS thinks and feels like us?

He says the GS is us, so of course they think and feel like us. But I agree, I see no reason why they would find a need to create a fictional world framed in some past century, a simulation of the scale he suggests. It's not like it would produce any actual events that took place in the history of the GS world. What would be the staring date of such a sim? Last Tuesday?

Maybe we are characters in someone's video game

Not possible given your stated beliefs. Only the players can be conscious, not the NPCs. But actually, I have suggested similar things myself, claiming to be a p-zombie in a world where not all are, because I don't see this hard problem that so many others find so obvious. Clearly they have something I don't. So OK, I'm an NPC.

Maybe they are the cause of sickness and war and suffering. Maybe they are sadists. That's a more realistic hypothesis than that we're an ancestor simulation.

So a sim run by a world devoid of sickness and war, but populated by sadists with a need to create ant farms to torture? I can't see a world populated by such beings being free of natural misery.

[Tegmark] says the world literally is a mathematical structure.

Yes. He recategorizes mathematics. The hypothesis has severe issues, but category error isn't one of them.

They are abstract.

Not under MUH they aren't. Being abstract requires them to supervene on an abstractor, making them non-fundamental.

But even a Boltzmann brain is not a mathematical structure.

It would be be part of one under MUH, just like one would be part of our universe if there were some out there.

By the time I was done last night I rejected your concept. Same reason that my chess pieces do not care if they get captured or win or lose the game.

OK, you you have a definition of 'me' that doesn't include any avatar.
Does your physical body enjoy the ice cream? You didn't answer that question. I want to see if you're consistent.

Yes pansychism. How else can the rock, the baseball, the chess pieces, and Ms. Pac-Man experience my pleasure in the game?

By being an avatar of a mind, but that isn't panpsychism I think, but I don't really understand that view. I suppose the rock is no different from a chess piece. I cannot move it by mind alone, but that's also true of my fingers.

I think you are not convincing me of this thesis, though you did have me going for a while last night.

You seem to include Ms Pac-Man as you. Isn't that what you said?

Yes, I can extend my definition of 'me' to any boundary I wish. It's mostly just a language designation. There are no physical rules about it.

The Chinese room speaks Chinese, who am I and who is Searle to say it doesn't understand what it's doing?

Yes, the system understands Chinese. A part of the system doesn't necessarily understand it, just like the CPU of my computer doesn't know how to open a text document. That doesn't mean that the computer doesn't open the document, unless that you define 'to open a document' as only something a human does, and an unspecified alternate word must be used if the computer is doing the same thing.

That's the argument against my position. My Chinese friend speaks Chinese and my Chinese room speaks Chinese, what's the difference.

The Chinese room, as described, seems to be in a sort of sensory deprivation environment. Surely there are questions you can ask it that bear this out. They have machines now that officially pass the Turing test, and some of the hardest questions are along such lines.

Well we're back to LLMs.

An LLM cannot pass a Turing test. Something like ChatGTP does not claim to understand language. It's not how they work, but maybe it's not how we work either.

I'm willing to stipulate that the Chinese room is as fast as it needs to be. It still doesn't understand Chinese.

OK.

I thought VR is Descartes's clever deceiver, who gives me an illusion of all my experience, yet my mind is still mine. And Sim says that my minds also is simulated/instantiated by the GS so that there really is no me outside the GS.

Yes, like that.

Memory?

If Pacman was fully immersive, and I had been playing all my life, then I am essentially a mind connected only to pacman. If the game is unplugged, then all the hookups are still there, but I am left in a sensory deprivation state. If not hooked to a different feed, then it stays that way. I of course have no control over it. I cannot take off the VR headset because the connections required to do so have been severed in order to connect fully to pacman.

If by "computer" Bostrom means something other than a computer as commonly understood, he should say that explicitly.

Pretty sure he means 'as commonly understood'. It doesn't mean that all sim theories suggest that, but with him it kind of does.

So my remarks on computability stand. Bostrom's thesis that the world and my mind are computational, as the word is understood today, is an unwarranted and probably false assumption; and in any event, needs evidence.

One could argue that the claim that consciousness is not computational is the one in need of evidence. I mean, a perfect simulation of our physics is not computational, but consciousness seems to operate at a classical electro-chemical level, and that is computational. I don't assert it to be thus, so it's a possibility, not a hard claim.

Yes, for things I haven't even noticed yet. But I think an explanation is needed if I am in a place I've never been, write a list of what I see, and another person in the same situation puts the same things on their list. — Patterner

My example is memorizing words/symbols without knowing their meaning, only to learn later how to read them. That's proof of information independent of your mind, a sort of refutation of solipsistic idealism.

If they are also asserting mind and consciousness can come from matter somehow, they have an even higher burden of proof. — RogueAI

Bostrom seems to presume this. If they do manage to simulate a human enough to appear conscious, those that deny consciousness can come from matter will simply deny that the simulated person is conscious. A successful simulation won't change their opinion.

Me? I make no such claim. — fishfry

No, not you. No quote of yours was in the bit there to which I was replying.

I say that consciousness is physical but not computational.

What do you mean by that? I mean, technically, none of physics is computational if done to a sufficient level of detail, but I don't think that level of detail is needed in a simulation.
Computation is classical and physics has been shown to be not.

What's the difference between [ID]and sim theory?

Not too much. Both are deliberate choices of interesting mathematics. The vast majority of possible universe are not interesting.

A simulation of gravity does not implement gravity. Simulations of brains therefore do not necessarily implement minds.

I didn't say implement them. I said that they would find the familiar pattern. If nothing is known about how that works, then you can't say it wouldn't happen with the sim.

The question is, why do we mock the Godly street preacher, and venerate the simulation theory TED talker?

There's a lot more veneration of the God talkers than you suggest here, and if Bostrom screamed his assertions from a box in a subway station, he'd get a lot less attention. He's getting mocked plenty in topics like this one. Bostrom is venerated at the Ted talk because the audience is full of people who's seen Inception and think that's what he's talking about.

Again, do you believe in intelligent design? Nothing provokes scientists more than that idea, they hate it. While gladly advocating simulation theory.

I'm gladly advocating it?? Bostrom claims we are in a sim of us: The world simulating us is the same as the one simulated. That's not ID since the design is already made and it is just mimicry. But in general, if you admit that we know nothing of the world running the sim, then the idea is no different than deism.

I see no difference between "God did it" and "The Great Simulator" did it, except that the GS is required to be a computation

Is it? If we can know nothing of those running it, how do we know it is a computation? At what point does it cease to be sim theory and just become straight up god:"whoomp, there it is" theory?

It seems a lot of my answers agree with yours, but your tone suggests disagreement with my replies.

Simulation theory says we are computations. That can only be understood as computation as we currently understand it. Turing machines, finite state automata, etc.

OK. You have a tighter definition of the term. You must call it something else if it is done, but not done as computation as you currently understand it. Do quantum computers qualify? Are they (if one is actually created) beyond our current understanding? Can they run a simulation, or would a different world need to be used? Can a quantum computer solve the halting problem for a Turing machine?

I mean, the god people do it all the time. God created physics, be it computable or not. Time as well, and general causality. That sounds an awful lot like a simulation mechanism to me. Old school says the sim began ~6000 years ago, but lately, in an attempt to avoid all out denial of science, they've backed off to a view of the project starting at the big bang, and perhaps with initial conditions that bring us about, because it's all about us after all.
That's a big difference BTW between god and a sim: A sim is run to see what happens, to gain information. God creates something where he knows exactly what will happen, and he wants that to happen. He gains no knowledge by running the universe experiment, at least not the god typically asserted.

Well then you are agreeing with me. It's a theological claim.

Deism isn't theological. It would be if those running the simulation implemented say a moral code which they expect to be followed by the subjects being simulated, "or else ...".

So the Great Simulator doesn't ask Abraham to kill his son?

That's messing with the simulation, violating the causality rules and such. If it works like that, then its a VR for the great simulator, and the rest of us are NPCs being asked to kill our sons.

But Tegmark's MUH is such a category error that I can't imagine he's serious.

Him redefining the categories is not a category error. You're begging a different definition. Mathematics is not a map in the view.

The MUH predicts that the majority of consciousness are Boltzmann brains, reducing the hypothesis to where it cannot be simultaneously believed and justified. That's a huge hit to the idea, and one which he must be aware, and has perhaps attempted a refinement, but it wasn't addressed in the book.

But now we know better. It doesn't need creation, only simulation!! /s

A simulation is a created thing. It exists in time. There's no evidence that our universe exists in time.

Oh I see your point! Thank you for explaining that. She gets her consciousness from me. I enjoy making Ms. Pac-Man eat the dots. I can see that. But Ms. Pac-Man does not have an inner life.

You see that Ms Pacman is you, but you still deny your inner life?

My experience is her experience.

A bit like you saying that your experience is the same experience had by the body of fishfry. Well, fishfry body doesn't have experience separate from 'you', and similarly Ms Paceman doesn't have separate experience. She does become a zombie while the game isn't being played, zooming around randomly and getting killed in short order.

Is this a form of pantheism? I enjoy throwing a rock, and by your theory, the rock enjoys being thrown.

It does? Where did I say anything like that? Because I intentionally caused it to move? That's different than me being the rock while doing so, making it move on its own.
Pantheism? What's that got to do with it? Do you mean panpsychism?
A dualist has a mind and a body, and typically the body has presumed boundaries which usually don't include the rock, but there's no actual hard definition of where the boundary is since there's nothing physical about it. So for instance, are the clothes I'm wearing part of me? The usual presumption is yes, despite that probably not being the answer if it is asked as a question.
"Where does 'you'" physically stop? It's more of a language thing than a physics thing. I typically don't include the rock as part of 'me', and you probably don't either. I could open an entire topic about this.

But that's his argument against the Chinese room understanding Chinese. He says that we humans provide the meaning or intentionality. He says that the room does NOT have meaning or intentionality.

Searle also plays the game of refusing to apply a word to something nonhuman doing exactly what the word means when a human does it. That's begging his conclusion.

I looked at the wiki page and the argument seems to have been updated. The guy doing it (instead of the computer) cannot pass the Turing test since speed is an issue. Somebody who takes 20 years to reply to 'hello' is probably not going to pass a Turing test. Speed up time in the box and this objection goes away. No, the man in the box does not understand the conversation any more than does the CPU in the AI or than does a human brain cell.

Physics is the historically contingent human activity of Aristotle and Newton and Einstein explaining why bowling balls fall down.

Not talking about a human activity. I'm talking about the actual nature of the world, not how we describe that nature.

Ok ... not entirely sure about this. Isn't it the opposite? If my mind is primary and my experiences are an illusion, the illusion-giver, the simulator, may withdraw my reality at any moment.

That's a description of VR, not a simulation. Mind is primary in that scenario. It is real, and the rest illusion.

With sim, the world behavior (physics) is primary, and things proceed according to the rules, without outside interference or intentionality. I have done both kinds. They're very different.

If there's a simulator, they may get bored of providing me with this interesting reality and unplug me, and I'll cease to be.

That sounds more like a sim, yes. If they unplug it, everything/everybody is gone, but perhaps still on disk somewhere. It could be restarted 2 years from now and the simulated beings would never notice the interruption. They very much would notice if it was a VR.

And if VR is true, the same thing might happen, but my untethered mind will remain, but devoid of experiences.

It would be like quitting PacMan. Devoid of experience of the pacman world, but not devoid of experience.

I did a short breakdown of the topic here: — Lionino

That goes down a rabbit hole of info and posts to even more topics. Good reading.

I was looking at Steffan's slideshow, and it goes into how Cantor's axioms are paradoxical because the set of all sets has smaller cardinality that the set of all subsets of that set. But for similar reasons as have been discussed in this thread, I'm not convinced by it since the axioms only seem relevant to finite sets (similar to a sequence having a first and last step only being relevant to a finite set of steps), and none of the sets in the paradox is finite. So it's a bit like saying infinity squared is larger than infinity, which it isn't.
Far be it for humble me to not be as distressed by this as the hardened mathematicians. I take their word that this has more teeth than I see.

Also of interest is the mention of Godel demonstrating that a goal to find a complete and consistent foundation of mathematics cannot be reached. Does this mean that there cannot be one, or just that we cannot know it to be complete and consistent?

Yes, and I think that Lionino may have been protesting at such ways of talking. If one is not a platonist, the way to say what you want to say is to conceptualise "real" in a non-platonic way. — Ludwig V

I have issues with what most people label 'realism', so I'm probably further from platonism than are most. Real is a relation to me, and I use the word that way.

I've noticed a variety of extensions of the use of "=" lately, so I'm sorry if I misused it.

OK, there can be more than one use of the symbol. We seem to not be in disagreement.


The modal fictionalism link is appreciated.

I don't think the calculus is relevant. — Ludwig V

Well, when was the notion of limits of a series introduced? Not back then I think. I'm not an expert in the history, but Zeno was definitely using techniques beyond the state of the art at the time. Good for him.
There are people today that say that there are no real infinities, whatever that means. I think this might be one example of such an assertion.

If you accept that Twin Earth is not physically possible

Where there's not-water? I accept that as a physical impossibility, yes, but overtaking a tortoise is not.

there's no need to argue about the sun example. Maybe your imagination is richer than mine.

A list of valid options is not a definition of a state.
— noAxioms
Parent = (Mother or father).

Well illustrate. A list is not a parent, so I disagree with the '=' you put there. I'm sure there is a correct symbol to express that any member of that list satisfies the definition of parent.

Tegmark must be trolling. — fishfry

I replied to this in the simulation topic since discussion of it seems to be of little relevance to this topic.

But you [Michae] just proved P2 yourself! You agreed that under the hypothesis of being able to recite a number at successively halved intervals of time, there is no number that is the first to not be recited.

This proves that all numbers are recited. — fishfry

The two of us also seem to be on the same page.

I said that time stops? — Metaphysician Undercover

Not in those words. "Does not allow for a minute to pass", like somehow the way a thing is described has any effect at all on the actual thing.

The specifications do not allow for a minute to pass, that's the problem. — Metaphysician Undercover

Anyway, I see nothing in any of the supertask descriptions that in any way inhibits the passage of time (all assuming that time is something that passes of course).

I don't think so. I said that in the scenario of the op, 60 seconds will never pass.

The OP scenario is pure abstract, and it directly describes a state beyond the passage of a minute.

But clearly time does not stop. In that scenario, time keeps passing in smaller and smaller increments, such that there is never enough to reach 60 seconds, but time never stops.

Ah, it slows, but never to zero. That's the difference between my wording and yours. Equally bunk of course. It isn't even meaningful to talk about the rate of time flow since there are no units for it. The OP makes zero mention of any alteration of the rate of flow of time.

So you deny that numbers exist? Really? — Ludwig V

Not to put words in anybody's mouth, but such a statement depends heavily on the definition of 'exists'. For instance, does the number 37 have a location somewhere in our universe? When was it created? That references a definition of "is a object in our universe". If you define 'exists' as 'is an abstract concept in some mind somewhere', then 37 exists as long as somebody is thus abstracting. It's still a version of 'is part of the universe'.
I am not really sure of the definition Lionino is using. I didn't get it from the brief context.

Look at Tegmark's view mentioned above. He is definitely using a definition of 'exists' that doesn't supervene on our universe, and suggests that the reverse is the case.

Patterner bumped this old post, so I tracked down what was being referenced.

I'm not making any claim other than we know mind and consciousness exist. It's up to the people asserting mindless stuff (i.e., matter) exists and consciousness and mind emerge from it to prove it. — RogueAI

Minds/consciousness can't come from matter, therefore simulation theory is false.
— RogueAI

How do you prove that?
— Benj96

Why is the burden of proof on me? We know mind and consciousness exist. The existence of mind-independent stuff is simply asserted. I would like to see a proof that this stuff exists. Something a little more robust than "go kick a rock". — RogueAI

You're making the strong claim that mind/consciousness can't come from matter, so the burden of proof of that claim is definitely on you. If Bostrom makes the claim that mind/consciousness does emerge from matter, then the burden of proof of that is his. I'm not sure if he's making the claim directly, but his sim argument depends on it, and he's claiming the sim argument, so the burden is still there, as it is on you for your strong claim.

You make a second claim, that sim theory is false if your assertion is true. To me, that's another thing in need of proof. You arrange matter into a person and somehow a mind thingy finds it. What's different about the simulation that the same thing wouldn't happen, that the simulated thing would be conscious the same way you claim to be, despite it being attached only to a simulated physical?

I agree that 'klick a rock' is a catchy phrase, but since the experience of stubbing your toe is identical in the two views, kicking a rock demonstrates nothing. It seems to be a cheap counter to rocks being declared not-real.

Is the idea that the many minds/consciousnesses all think up the same things that we generally take to be mind-independent stuff? — Patterner

That's a far stronger argument for mind independent stuff. It doesn't refute solipsism since there aren't other minds also agreeing on the rock that you haven't even noticed yet. But similar arguments can be used to refute solipsism.

Why do people who reject God accept the Great Simulator? — fishfry

More to the point, why would anybody (even Bostrom) accept the SH? People choose a view either because there is evidence or because they want it to be true. The former is a rational motivation and the latter is rationalized. Bostrom's argument seems to attempt to bend the facts horribly to make the hypothesis plausible. This suggests that he wants it to be for some reason, but I cannot fathom why somebody would want to actually believe that. OK, I see why one might want to appear to believe it: Because of the popularity of the idea from movie fiction. He has gained money/status/notoriety from pushing a view that nobody else is in a coherent manner. Elon Musk is a decent example of an incoherent hypothesis, and he's not doing it for the notoriety that he already had. Without knowing it, he pushes for VR, and I can see reasons why somebody might choose that.

The GS is just God constrained to computability.

The world simulating us is not constrained to the computability laws that constrain our world. It is thus constrained in Bostrom's view, but not in general. It's sort of a computing version of deism. The creating simulator starts it up, but then steps back and never interferes and lays no demands on what the occupants do, nor does it make any promises to them. The typically posited god usually does have promises and demands, but not necessarily under deism.

I laid out my case that Tegmark is a troll here ... — fishfry

I haven't got round to replying to that endless topic yet, but Tegmark is more appropriately discussed here since it has little to do with supertasks.

You say category error: Please explain that without begging a different view. You do explain it there, but you are very much begging a different view when doing so. Tegmark is saying that mathematics (not any mental concept of it) IS the territory. Our abstract usage of mathematics is the map, but that abstraction is not what is the universe.

How does he get around the category error problem, confusing the map with the territory, or the program with its execution? My hat is off to you for having read the source material.

It's not much different than all these centuries where the universe was considered to be an 'object', a thing contained by time and in need of creation. They all of a sudden a new view comes along and the category changes. It isn't an object created in time, but rather a structure that contains time. Most people still hold the 'contained by time' view since it is more intuitive. Tegmark is doing something similar: changing the categorical relations. Refute it from its own premises, but not by begging different ones.

You give your browser far too much credit. It passes no judgment on anything. You are the one who has judgment. The browser just flips bits on your computer to implement certain communication protocols that it uses to exchange data with a web server. And the data has no meaning, it's just a long string of bits. Humans give it interpretation and meaning.

Your refusal to apply the language you use for human activities to something non-human doesn't mean that the non-human thing isn't doing them.

Does Ms. Pac-Man experience pleasure eating white dots,
Obviously yes.
— noAxioms

You can't believe that. Are you joking with me or making some kind of point I'm not understanding? It's not possible that you believe that literally.

Ms Pacman is you. It's a VR game, and you enjoy eating the dots, else you'd not be cramming quarters into the machine. It is a straight up case of dualism. Ms Pacman's consciousness is yours. She is the avatar, who doesn't enjoy the dots any more than you claim your physical avatar enjoys the ice cream.

Searle's rolling in his grave and he's not even dead. That's not true. Searle denies that bit-flipping instantiates intentionality or feelings like pleasure.

Searle says exactly that, since what your avatar does instantiates feeling in your mind. Intentionality comes from that mind and not from the avatar. Likewise, Ms Pacman makes no choices on her own, since the intentionality comes from the mind (you) who is obviously very much enjoying eating the dots.

A physicalist, which Searle is

Perhaps this is the disconnect. In what way is Searle a physicalist? Usually the term is used for a physical monist: All physics (including people) operate by the laws of physics, every bit of which is arguably computational.; Searle perhaps posits a different kind of matter that he still labels 'physics', but the physics community doesn't since there's been no demonstration of it.

I'm still disturbed by the things you claim to believe.

Have I claimed beliefs? Do I believe the rock exists independent of me? Do you know enough of my beliefs to answer that?
What's the point of sharing them? I try to understand the alternatives, and point out those alternatives to those asserting that some particular view must be the case. I don't think I assert that any particular view must be the case, but maybe I do sometimes. Like I said, I shy away from something like BIV due to it being empty of information, but not because it must be otherwise.

Anyway if simulation theory is true, we're all characters in a video game

No, that's if VR is true. SH is not modelled by a video game.

So when someone describes the situation in a way that seems to make that fact impossible, why don't we just reject it as inapplicable? — Ludwig V

I do, but Zeno's division of the task didn't seem to make anything impossible. To read Aristotle, Zeno seems to believe in the discreetness of anything of magnitude, directly contradicting Aristotle's physics of the day, which were his opinions pretty much by definition. Much of his opinions held for millenia. Some still do.
Also keep in mind that physics was absolute back then, and calculus was unheard of.
So Zeno's premise that in any task of changing location, one must first go to the halfway point. Zeno seems to have put that up there as a ridiculous premise, one in which he didn't believe. It was an attack on Aristotle's position which would find no fault with the statement. Given Zeno's beliefs, the premise above is false, and he attempts to demonstrate why, but of course he can only do so by begging his own opinion, which is the second premise that I've been going on about.

But we allow physical impossibilities into fiction all the time. They even crop up in philosophical examples. "The sun might not rise tomorrow morning"

Not an example of a physical impossibility. Yes, i agree that physical impossibilities can be turned into fiction. Did I say otherwise?

Your point about the final state not being defined is about logic, not physics (despite some people thinking that it is about physics).

The state of Achilles is that he is even with the tortoise. It's admittedly not final because he continues on after the task of overtaking it is complete and takes the lead. There's nothing about that where physics stops being relevant.

The lamp example? That isn't physics. Never was.

In any case, the final state is defined. It must (on or off) or (0 or 1).

A list of valid options is not a definition of a state.

Wouldn't it be more accurate to say that it is undetermined?

Synonym?

But it would be absurd to say that every state in the series is indeterminate.

They are, or at least the existing ones are. None of the ones you listed was an existing step.

The time length is irrelevant. — Metaphysician Undercover

Says the proponent that time stops.

See my comment above. I suspect Zeno believed his premise to be false, that one must first get halfway before getting to the goal. He was trying to illustrate this belief by driving Aristotle's assertions to absurdity, but he must beg his own beliefs to do this.
If there was a better worded argument provided by Zeno himself, perhaps Aristotle didn't convey the full argument, in the interest of waving away a suggestion that he is wrong. So many modern mathematical tools were not available to them back then.

I gave you Aristotle's wording.

To me it was just another wording, but apparently so since I see it referenced verbatim on so many discussions. Interesting is the total lack of mention of the tortoise.

He rejects most of the arguments because they contradict his own assertions.

The matter of instants appears irrelevant here, and the problem seems to be with the assumed nature of space, rather than time.

The argument is the same with space. He says "time is not composed of indivisible moments any more than any other magnitude is composed of indivisibles". Space qualifies as an 'other magnitude'.

Like above, noAxioms insisted Zeno did not conclude that the faster runner could not overtake the slower, — Metaphysician Undercover

I said no such thing. Zeno very much is reported to have concluded such things.

requires that consciousness is computational, a point I strenuously disagree with, with Penrose and Searle on my side.
— fishfry

Why do you think it's not computational? — RogueAI

With the Penrose & Searle reference right there? The answer is obvious. Bostrom obviously doesn't hold this view.

So you DO have axioms :-) — fishfry

I hold them to be true out of necessity, not because they necessarily are. Another one then I forgot to list: No magic. "I don't know, needs more investigation" is a far better answer than the god of the gaps explanation. Every time one of those open questions finally gets answered, it's never magic. The magic explanation is thus far on the wrong end of a shutout.

Why does the sun cross the sky each day? God carries it thus. What's have we learned since? Clue: It isn't that Earth goes around the sun, since it doesn't do that each day, yet that's the rebuttal typically given.

Likewise Tegmark's mathematical universe. An even more obvious troll. — fishfry

You may not buy into Tegmark's suggestions, but that doesn't make him a troll. I don't agree with him either, but I still read the book and find it revolutionary. His attempts at empirical evidence are completely faulty, but one is expected to pony up evidence to bump the idea from interpretation to actual 'theory'. He doesn't call it that, only calling it 'hypothesis', but even that word implies falsifiability.

Is your web browser passing judgment on the opinions you post to this site? — fishfry

Matter of time. Right now it only passes judgment on my choice of sites on which I choose to post my opinions.

Does Ms. Pac-Man experience pleasure eating white dots,

Obviously yes. As a Searle fan, you should know this. The question is does Blinky experience pleasure eating Ms Pacman? Blinky is an NPC. Ms Pacman is not. The answer there is no only because such experience would provide no benefit to Blinky, so there's no reason for it to be there. This would not be the case in Bostrom's sim, were it possible.

the brain does not operate by the same principles as a Turing machine.

Agree, but a physicalist would say that the brain could be implemented by a Turing machine, just as it could be pencil and paper. Arguably, the latter might actually be more efficient. Turing machines are not designed for practicality. They're a model of computability.

@Joshs Just some side comments on the Zahavi quote

The universe is said to have existed for many billions of years. — Zahavi

That comment (the verb 'exist for', not to mention the tense, implies a universe contained by time. Physicist probably say this all the time, but accepted physics doesn't word it that way. Most people don't reach for B series speak except for explicit need. But the prevalence of A-series in common language goes a long way toward reinforcing the A view.
So are we going to say "the temporal size of the universe is bounded only on one side, and fuzzily bounded on the other"? Who wants to hear that?
All this commentary of mine seems irrelevant to why you posted this.

Husserls fundamental claim is that our experience of a temporal object (as well as our experience of change and succession) would be impossible if our consciousness were only conscious of that which is given in a punctual now, and if the stream of consciousness consequently consisted in a series of isolated now-points, like a line of pearls. If this were the case, were we only able to experience that which is given right now, we would, in fact, be unable to experience anything with a temporal extension, that is, anything that endured. This is obviously not the case, so consequently we are forced to acknowledge that our consciousness, one way or the other, can encompass more than that which is given right now. We can be co-conscious of that which has just been, and that which is just about to occur.

OK, but none of this seems revolutionary. Yes, being conscious of what has just been is what short term memory is for. Being conscious of what is about to occur is the ability to predict, a critical ability if one is to be more fit. The quote calls it imagination, not memory. 'Imagination' probably better describes the predicting end and not so much the direct perception of temporal objects. I suppose imagination is a term that can be used to describe the recall of some immediate memory.

I see a reported conflict between the Brentano view and Husseri's, or rather I don't see a conflict. The seem to be slightly different words for the exact same thing, a difference being at a level that, well, seems irrelevant at least to this topic.

Also, there is no perception of a punctual 'now'. There is process to be had, which delays it a fraction of a second, give or take. Anything perceived is already past.

And not only that, we find a consciousness that still hears the first two notes (it neither imagines nor remembers them).

Good example. I don't see the difference between the 'this' and the 'not that'. It seems like being nitpicky about the words to describe the psychological experience of temporal things. None of the article seems to in any way be relevant to this experience being different from one interpretation of time vs another, which is why I thought the topic was brought up.

You have accidentally quoted Michael as me. — Tom Storm

So I have. Fixed, sort of. Sorry about that.

You seem to get what Josh is conveying more than I. All I see is different words that don't really contract each other. I agree with both sides, and that's probably wrong in some way.

Yes, it affects how we think of them. It doesn't effect the situation, despite all the assertions to the contrary by several members.
— noAxioms
Yes - unless it is a fictional situation - whether in the philosophical or the literary sense. — Ludwig V

I must disagree there. If there are two different descriptions of a fictional situation, and the description affects the thing being described differently, then they're describing two different things, not the same thing in two differnt ways.
The tortoise being overtaken is fiction, but mirrors real physical situations, unlike almost all the other examples in this topic. Describing the motion of Achilles as normal or as a supertask has zero effect on the ability of Achilles to overtake the tortoise.

A thought experiment is a valid method of deriving conclusions from premises. They only get fictional if the premises are faulty, such as the lamp, a device which cannot physically operate as described.
— noAxioms
That may explain why I have been confusing them. Thanks for that.

I must clarify that the lamp itself is physically impossible, making it fiction. I said 'faulty', which it is not. It measures something undefined, so it isn't a contradiction (a fault) that the final state isn't defined.

I have wondered whether one could replace the Thompson lamp with a question, such as whether the final number was odd or even.

Exact same scenario. But it's like asking if the smell of lavender is odd or even. There isn't a number that corresponds to the quantity of steps taken.

The lack of a first step does not prevent the beginning of the task
— noAxioms
It literally does. — Michael

This is exactly why I asked for your definition of 'start' since you seemed to be committing an equivocation fallacy between two definitions. You copped out and gave a synonym (begin) that has the same two definitions.
Is it Sv1 or Sv2? Because you are using both here, playing a language game.

I am saying that the lack of a first step does not prevent the beginning (Sv2 definition, 'transitions from not doing the task to doing it') of the task. You reply that it literally does, but Sv1 is the literal definition (the finite, 'has a first step').
I would not state that the lack of a first step does not prevent the first step from occurring (Sv1). That would be a contradiction indeed.

You ignored it and just said "when the time comes I say the next number". That doesn't explain how the recitation can begin without a first number to say.

You cannot show how that description doesn't work. Your only argument is that it doesn't perform a first step, but the description doesn't mention the need to do so, so the criticism is inapplicable.

I am right now trying to recite the natural numbers in descending order but am silent because I cannot begin.

You are not. It isn't a physically possible task. If you want to do a physically possible one, do Zeno's dichotomy. It's easy. You do it every day. The task is started despite the lack of a first step.

If you take the physical impossibliity away, then you failed because you didn't recite each number at the prescribed time. Your choice not to do so. You didn't follow my procedure. If it's been a minute, you admit to not following it.

Consider the infinite sequence {0, 1, 0, 1, 0, 1, ...}.

Now consider reciting its terms in reverse. — Michael

Undefined. You give no indication of when each number is to be recited. When do I say the 71st to the last zero for instance? I can answer that with a scenario that is properly described. It isn't a supertask as described.

Here's what Aristotle reported:

The second is the so-called 'Achilles', and it amounts to this, that in a race the quickest runner can never overtake the slowest, since the pursuer must first reach the point whence the pursued started, so that the slower must always hold a lead.
— Aristotle Physics 239b 14-17 — Metaphysician Undercover

That's apparently what somebody else reported about what Aristotle reported. I've seen it conveyed about 20 different ways. This particular wording says 'never' and 'always', temporal terms implying that even when more than a minute has passed, (we're assuming a minute here), Achilles will still lag the tortoise. The logic as worded here is invalid for that reason since the argument doesn't demonstrate any such thing. I've seen more valid ways of wording it (from Aristotle himself), in which case it simply becomes unsound.

How is this different from what I said?

It isn't much. I just didn't like the fact that the quote didn't match the site linked. Too bad Zeno's original argument is gone. Maybe he covered his ass better than the summary provided by somebody paraphrasing Mr. A.

Without axioms it's difficult to get reasoning off the ground. You have to start somewhere, right? — fishfry

I start with a few.
1) It's not all a lie. I mean, I can't know that, but if it's all crap, then I can know nothing regardless of how I interpret the lies, so I have no choice but to give weight to the empirical.
2) It's not about me. If I am the center of the universe, the rest is probably a lie. So I pretty much find that any view that puts me, humanity, Earth, the universe itself, as the center of something larger, to be unproductive.

Descartes apparently worried about it all being a lie. I reject that road only because it is untravelable, not because it is wrong. But it seems that modern science has thrown a cold paid of doubt on the validity of "I think therefore I am".

VR says that all you know is potentially lies. You are not of this universe, but rather you are experiencing it. All very dualistic.
If you think about it, the view can be empirically tested. Not so much with the simulation hypothesis.
— noAxioms
Yes but everyone agrees with that. There's a world "out there," and we experience it through our senses. — fishfry

Not sure what you mean by empirical testing here.

As I said, one can empirically examine the causal chain that makes the body walk for instance. In a VR, it does not originate in the brain of the avatar, but external, from the mind controlling the body. Say you're playing tomb raider. Open up Lara Croft's head. No brain in there, or if there is, it's just a prop. None of the stuff she does has its cause originating from there.
Why does nobody pursue such investigations? Is technogoly still so backwards that it can't be done? They already have machines that can detect a decision having been made before you are aware of having done so yourself.

It's always been unclear to me which aspect of simulate/VR Bostrom is arguing.
Definitely the former. But Elon musk is arguing for VR, and references Bostrom's paper to support it, so he has no idea what he's talking about.
— noAxioms

Right. And I saw a TED talk where George Smoot, the guy who discovered the cosmic background radiation anisotropy, was enthusiastically advocating simulation theory. Neil deGrasse Tyson too. A lot of people who should know better say trendy things for no reason at all. More arguments against simulation IMO.

Trendy, yes. Kind of dumbs down the validity of any scientific discovery. Why would a simulation choose to display CMB anisotropy if that isn't what a real universe would look like?

I've seen the argument -- perhaps this wasn't in the original Bostrom paper, I don't recall -- that we should consider Pong, the original video game. versus the amazingly realistic video games of today — fishfry

I think that example was being used as an illustration of Moore's law, and not as support for a VR hypothesis.

Yes. Let's talk about this over there. — fishfry

I replied to much of your post, but all over there.

Just the ordinary meaning of "start", e.g. "begin". — Michael

In that case I reject your premise. The lack of a first step does not prevent the beginning of the task, which is simply the transition from the time prior to any of the steps being taken, to the time during which steps are being taken.

You ask me, right now, to recite the natural numbers in descending order. How do I begin to perform this supertask? — Michael

I described exactly how to do that, and you found no fault with it, choosing instead to try a different wording of your additional premise. Why does my description fail? What step is missed? None, and it's done in finite time, so you apparently cannot find fault except by asserting additional premises, all of which take the form of asserting a need to perform a step that by definition doesn't exist.

The paradox is like this. — Metaphysician Undercover

I know the story. You seem to have reworded it for your purposes, since the quote you give does not come from that site, but the site also seems to be conveying the story in its own words, not as reported by Aristotle.

Zeno concludes that the faster runner cannot overtake the slower.

Yes, and without justification, or at least without explicitly stating the additional premise that makes the conclusion valid.

Other quote:
... And it seems that Achilles will always be stuck in this situation.

Same thing. Does not follow.

Funny that the animation on that site below that quote shows 'lightning fast' Achilles moving at only twice the speed of the tortoise. It also shows Achilles slowing down to pretty much a halt, which is why he never passes the tortoise in the animation.

Are we resorting back to the beginning of the discussion here? If you cannot counter my posts, you just start over with the original story? Yes, you can keep the topic going a long time this way, but you're not helping your case.

But different descriptions of the same situation can affect how we think about that situation. — Ludwig V

Yes, it affects how we think of them. It doesn't effect the situation, despite all the assertions to the contrary by several members.

An additional difficulty, I suspect, is that our descriptions are fictional (sorry, thought-experiments)

A thought experiment is a valid method of deriving conclusions from premises. They only get fictional if the premises are faulty, such as the lamp, a device which cannot physically operate as described.[/quote]

According to this, "many philosophers have argued that relativity implies eternalism. Philosopher of science Dean Rickles says that, "the consensus among philosophers seems to be that special and general relativity are incompatible with presentism." — Michael

Relativity does give a strong suggestion, but it is going too far to assert full incompatibility.
The two premises of SR is where the trouble is. I googled "premises of special relativity"

PBS came up first: "the same laws of physics hold true in all inertial reference frames and that the speed of light is the same for all observers"
This suggests a metaphysical assumption. If the laws actually are frame independent, then presentism is wrong since it requires a preferred frame.
But if the same two premises are more loosely worded, then presentism works:
The same laws of physics appear to hold true in all inertial reference frames and that the speed of light appears the same for all observers.

Now it's about appearances, about empirical evidence, about science, not philosophy. This is fully compatible with presentism since all it says is that there may be a preferred frame, but there's no way to figure out which one. The one-way speed of light is not c in any frame but the preferred one, but there's no way to measure the one-way speed of light.

The rest of the theory is unaltered since the only difference between the interpretations of time is that eternalism assigns identical ontology to all spacetime events and presentism assigns different ontology to them (each getting one of four values). None of relativity theory rests on the ontology assignment given by some abstract theory, so there is no incompatibility with relativity theory.

I have found fault with any posted falsification of presentism or eternalism, and I've seen plenty of both.

Do you mean that time is also an aspect of consciousness and therefore located in our cognitive apparatus (but that may be closer to Kant?). — Tom Storm

There are three kinds of time, and those that ask "what is time" never seem to realize it.

1) Proper time. This one is very much physical and real, and is what a clock measures. Proper time is frame invariant.
2) Coordinate time: This one is the abstract assignment of time coordinates to spacetime events and is thus very frame dependent. A calendar is a decent example of one.
3) Phenomenological time, which is the phenomenological experience of the advancement of the present. It is part of consciousness, yes, but also part of pretty much any system that interacts with its environment in real time, but the word phenomenological only seems to apply to the conscious cases. This one seems to be frame independent, and the various interpretations of time differ as to whether the phenomenon corresponds to any physical noumenon.

This IEP snippet may give you a sense of what I mean — Joshs

I read it all, and while I think it fairly clearly conveys what the common sense view is, it then declares itself to not be that, and what it is (the last paragraph) kind of lost me. I could not, from that, summarize what Husserl is trying to get at.

Does Bostrom actually address this distinction? — fishfry

Bostrom seems to presume that consciousness is computational, and leaves it undefended.
In such a simulation, nobody is being fooled.

In a VR, is it a lie to have the subject experience a world that is not the same world as the reality in which the mind exists? If so, most forms of dualism are arguably deceptions.

It is impolite to ask for an opinion, receive one and not replying. — Alkis Piskas

You're not the first in this thread to express disapproval of this practice. I noted it before I posted my first reply and didn't bother to address any of his post directly, knowing that he seems not to even read any of the replies to most of his topics.

I cannot start reciting the natural numbers in descending order because there is no first natural number for me to start with. — Michael

Given your reluctance to clarify the definition of the verb 'to start', I cannot respond appropriately to this statement. I gave a pair of options, or you can supply your own, so long as it isn't open to equivocation.

I'm pretty sure that one comes down to being able to split the pieces up into pieces that aren't measurable — fdrake

Your confidence in your own understanding is then stronger than my confidence in mind.

I still wonder (when I haven't anything more important to wonder about) whether Aristotelian physics is not fully applicable or not physics or false. — Ludwig V

Some of both, I'm sure. The impetus thing had to go (survived until Newton, not bad...), but one could argue that it is a poor description of inertia.

when we finally split the atom. (Which, you will remember, was by definition unsplittable).

The smallest thing still is. Unfortunately the word got applied to something that was a composite object, and they kept that instead of renaming the assembly and keeping 'atom' for anything fundamental.

I don't see the need for any other premise.Achilles is moving, and described as doing this in a way in which he will always have to move further before he can overtake the tortoise. — Metaphysician Undercover

Not always. Just a minute. I know, Zeno doesn't give the time, but we've been using a minute. The way the scenario is described has no effect on the situation compared to a different way of describing it.

Anyway, I deny that Zeno in any way suggests that the overtaking will never take place. He just says that another step always follows any given step.

Michael has added the verbalizing of the natural number count, but that doesn't change it taking only a minute.

The Romans thought mind was a flow, because they had great waterworks, and so forth. We live in the age of computation so we think we're computers. — fishfry

They can't both be right?

You're agreeing with my point.

I think I am, yes.

I've seen Searle argue that consciousness is physical but not computational. Some kind of secret sauce found in living things and not in digital circuits. Don't know much about analog computation with respect to consciousness.

Anything analog can be approximated with digital. But anything digital can be perfectly implemented with analog. Searle is perhaps referencing property dualism? I don't know if I got that right. Can't seem to articulate the differences between the variants.

As Descartes noted, I may be deceived, but there is an I who is being deceived.

I guess I'm even more skeptical than Descartes. I win! I didn't pick my handle for no reason. I try not to leave anything unquestioned.

So the VR theory doesn't solve anything at all, it leaves the mystery of what my own consciousness is.

VR says that all you know is potentially lies. You are not of this universe, but rather you are experiencing it. All very dualistic. The 'brain' in the body (if there is one at all, have you ever checked?) is not what's making any of the decisions.
If you think about it, the view can be empirically tested. Not so much with the simulation hypothesis.

It's always been unclear to me which aspect of simulate/VR Bostrom is arguing.

Definitely the former. But Elon musk is arguing for VR, and references Bostrom's paper to support it, so he has no idea what he's talking about.

The comment above (and my reply) belongs in the other topic. I see you posted more or less the same question there.

There is never a final tick in an infinite sequence, even if the sequence has a limit.

or not a first tick. Zeno's dichotomy very much has a final tick. I can make a scenario that has a first and last, and gets singular in the middle somewhere. Just illustrating the classical snippet: Never say never.

By phenomenological I meant phenomenological philosophy — Joshs

I looked up the SEP article on this, and I don't think I used the term incorrectly. It doesn't seem to presume any particular interpretation of mind. It says:
"In its root meaning, then, phenomenology is the study of phenomena: literally, appearances as opposed to reality."
This is what I am talking about. The phenomenal experience of say a person does not vary depending on which interpretation of time is 'reality'. The experience is the same, and has to be, else there very much would be an empirical test to falsify some of them.
That said, I do realize that some interpretations of mind are incompatible with some interpretations of time. Perhaps this is where you are coming from. My description of one of the interpretations of time conflicts with your beliefs about the nature of mind. That doesn't disprove anybody's view of either.

I am experiencing the present continuously. — Truth Seeker

I already acknowledged your stated opinion in this matter.

None of us can time travel to the past or the distant future.

SEP says otherwise, but I agree here. What most people think of as time travel is impossible. SEP for instance considers time dilation to be time travel, meaning all of us do it just by crossing the street and back. I disagree with this qualifying as much as you probably do.

how do we know that the past and the future exist? — Truth Seeker

They're all interpretations. By definition you can't know this. Only one view (spotlight) says the future exists, and its proponents cannot run a test to confirm the premise.

No, I'm saying that something with no start cannot start and something with no end cannot end. — Michael

This seems to be playing language equivocation games. You introduce the word 'start' here, undefined twice, once as a noun and once as a verb. Given certain definitions of both usages, I may or may not accept this additional premise you state.

The noun definition I will call Sn.
Sn1: The "start" of a sequence is a first step. This is exactly a bound, but you say 'No, ..." above, denying my calling it a bound, so you must mean a different defintion Sn2 of 'start' that this sequence doesn't have. I can't think of one that is distinct from a bound, so you need to help me here.

The verb is also used (cannot 'start'). Here I can think of at least two definitions:
Sv1: To start is to initiate the first step. This again is a reference to the bound.
Sv2: To to start is to commence the steps. There is a duration during which none of the steps has been performed, even in part. There is a duration when steps are being executed, and a duration when all steps have been completed. To start is to transition from the first to the second duration.

I suspect that you are actually equivocating multiple definitions of the verb to make your point. I mean, if you go with Sn1 and Sv1, then I actually agree with your added premise. A sequence lacking a specific step cannot execute the nonexistent step. That holds water. But then you equivocate to Sv2 and conclude that the existing steps cannot commence.

Your argument is effectively "by definition it has no start therefore it can start without a start" which is ridiculous

You are clearly using Sn1 as your noun definition here, which is a direct reference to the bound that we both acknowledge doesn't exist. This usage of the noun contradicts your opening word "No" in your post where you imply that your argument is something other than "an additional premise of the necessity of a bound to something explicitly defined to be unbounded". You contradict yourself.

Given the Sv2 definition for the verb, my argument is pretty much that, yes. It isn't ridiculous because I gave a precise description of how to do it. Your expressed ridicule isn't valid logic.

I am in the present continuously, not in the past. — Truth Seeker

OK, you are a presentist then. Under raw presentism, the past doesn't exist, and you can't 'change' what is nonexistent.

The eternalist view there is no 'the present' or 'the past'. There is a worldline that is 'you' and that worldline is as much a part of 2023 as it is 2024 or 2025. 2024 is not special in any regard. Hence my comment that 'you're already there', It was an eternalist statement, not a statement that makes sense given your interpretation of choice.

Under moving spotlight and growing block, you have a worldline very much like eternalism. You are there in 2023 as well as in the present. Your assertion above indicates that you don't buy into any of these worldline views.

Holding a strong belief in one of the options is just fine. But you can't critique the others if you don't understand them.

A problem I see here is what would we call “evidence” to either confirm or deny one of these theories. What would that look like? When I go “back to change” something existing in the past, when I get there, am I changing something which is presently in front me that is supposedly in the past. Is this evidence of presentism or block theory? — Richard B

Much of this topic seems to have revolved around the concept of 'time travel', which is defined differently from one interpretation to the next. In presentism, there is no past to go to. Under growing block, if you go to a place that isn't the present, how can you 'do' anything since you are no longer at the present? Do you bring the present with you? Such travel is very incoherent in growing block.
Under eternalism, time travel is any worldline that doesn't progress into its own future light cone.

Under any interpretation, time travel seems to be a state where the object is in a state that is causally a function of subsequent events: People having memories of future events for example. This is impossible under classical physics, so discussion of it will not yield any "evidence" about which interpretation is more likely.

preventing the murder of John Lennon. Can we do that? — Truth Seeker

Classical physics does not allow reverse causality. No physics allows non-local information transfer, and saving John would very much constitute non-local information transfer.

Well, I suspect that that sort of 'temporal change' would branch-off into another timeline (i.e. 'parallel' version of this universe) in which JL lived at least one more day — 180 Proof

Case in point. No known physics supports that. It again would constitute non-local information transfer. The branching is allowed under some interpretations of QM. The cause of it coming from subsequent events is not.

What is missing is the phenomenological experience of time — Joshs

The phenomenological experience of time is identical for every interpretation. That's why they're called interpretations.

If no particular step can overtake the tortoise, then the tortoise, by the described motion cannot be overtaken. Where's the need for another premise? — Metaphysician Undercover

Great. Then show the logic that concludes this, without resort to another premise.

Following from the described premises, the supertask cannot be completed.

That logic has not been shown. It's a non sequitur until it is spelled out.

It is logically implied that there is always further distance for Achilles to cover before overtaking the tortoise.

No such implication exists, and no such statement is made. Asserting this would be another premise, and one that makes no sense either. And yes, it would follow that the tortoise cannot be overtaken if this additional premise is added.

It clearly does not have a start. — Metaphysician Undercover

Your usage of 'clearly' implies you are referencing a second premise based on perhaps your intuition. What you may find 'clear' seems to be in direct contradiction with the first premise, I am presuming your 'clear' assumption is something on the order that there must be a first step, equivalent to asserting a bound to something explicitly defined as not being bounded. Of course you're going to run into contradictions if you add a second premise that directly denies the first premise. It isn't a paradox then, it's just wrong.
If that isn't your 'clear' premise, then state what you find so clear.

Michael also makes this mistake despite it being pointed out so many times.

There is no first natural number to start with. — Michael

Totally predictable response. We're like over 400 posts into this topic and you're you're stuck on the same fundamental mistake. You (as well as Meta above) seem to insist on an additional premise of the necessity of a bound to something explicitly defined to be unbounded. My method for performing the task made no mention of doing a first step, but it can be mathematically shown that any given step is done, and that the steps are done in order.

It is logically impossible to have started reciting the natural numbers in descending order.

An unbacked assertion, especially when I showed how to do it. Your presented 'logic' seems to be the argument above, declaring a second premise that happens to contradict the thing you want to find impossible. The logic to which you refer is only valid for finite sets, but you cannot learn this.

You can disprove it by naming a number that isn't covered by my procedure, or by naming a pair of numbers that are recited out of sequence, or some other such demonstration of a violation of the task as described. That's how you go about it when dealing with unbounded sets. Hilbert's hotel is a great educational exercise showing how mathematics deals with infinities.

As for the merely logically possible - as in logically but not metaphysically possible - , I imagine procedures like Banach Tarski. Turning a sphere into two spheres using only the material in the first sphere. But that's just because I can't imagine a concept of space used in metaphysics (like extension) that makes central use of non-measurable sets (things with ill defined extension in principle). — fdrake

I don't think it is the extension that is ill defined with that case, but rather a leveraging of the fact that the pieces are made of infinite points each, and you don't need 'more natural numbers' to count each one of them twice. I don't understand the Banach Tarski thing enough to know why 5 is a lower limit of the number of pieces.
Anyway, I chalk it up to another illustration of why the logical rules of bounded sets don't necessarily apply to unbounded ones. The posters above clearly cannot accept this, and so we go in circles.

Physically possible? That's getting hard. A universe that contains violations of the second law of thermodynamics is metaphysically possible. Like Lord of the Rings, Harry Potter. In the sense that there's a self consistent narrative going through those works of fiction whose behaviour is impossible to translate to our universe, those universes would be metaphysically but not physically possible.

OK, here you seem to use 'metaphysically possible' to mean 'possible in a universe with different physical laws'. But I don't find that very distinct from logically possible.

So when I hear Michael talking about the impossibility of a geometric series "completing" (so to speak) due to being unable to recite the terms in finite time,

I don't think he says that time is the issue. It is his insistence on the need to eventually recite the highest number, after which there are no more. That number doesn't exist, so the task cannot be done because it missed at least that one.

I have seen photos of black holes online — Truth Seeker

No you have not. Light cannot escape from one, so they cannot be photographed. What you see is probably X-ray radiation coming from the accretion disk.

The one presentist interpretation of relativity that I know about (an alternate theory that denies all the postulates of SR) calls them frozen stars because all the matter piles up around where Einstein would put the event horizon. Nothing can fall in in finite time, and the black hole will evaporate before the matter does, so no black hole.

That makes for an interesting way to prove to yourself that presentism is true or not, similar to a way to prove an afterlife. You fall into a large black hole. If you find yourself in there unharmed as Einstein suggests, then all forms of presentism are false. Problem is, just like the afterlife test, you cannot report your findings to the rest of the universe.

Moving spotlight allows them because there isn't a present time, only a present event (a single point in all of spacetime), and that point can be inside a black hole, so there's no contradiction. The other views posit a present moment in the universe, and no foliation of spacetime covers all events, so there are places (black holes) that cannot exist since the present will never get to them.

How do I visit last year?

You're already there.

I thought Moving Spotlight was the same as Block Time Theory. — Truth Seeker

It is. I say as much in my prior post. I've just never heard it called Block Time 'theory' before. The view cannot be logically argued for since it is epiphenomenal.

Apparently, Einstein subscribed to Eternalism/Block Universe Theory. Why would he do that?

Because it's the only one that allows relativity of simultaneity, something that derives directly from the premises of special relativity. Black holes don't exist except in eternalism and moving spotlight, and the latter is kind of a solipsistic view.

None of them are theories. They're all interpretations, and being interpretations, they cannot have empirical evidence.

If the past still exists, why can't we visit it and change it? — Truth Seeker

You can visit it. If you look at last year, you'll find yourself there. Of course the same goes for 2025, except that a view of that is not available in 2024.

This interpretation seems to me both the most evidence-based and consistent with human experience. — 180 Proof

You acknowlege that they're interpretations, which is means there cannot be evidence. Perhaps you feel otherwise. I know at least one that does, and cannot conceive of any other view.

Any presentist model (they all are except eternalism) is more consistent with biological intuition since an assumption of such is extremely advantageous for being fit. So it's built into living things at a very fundamental level. But that doesn't make it true.

While you're busy listing variants of presentism, you forgot moving spotlight.

On the surface, they all make the exact same predictions, so from that standpoint, there is zero empirical evidence one way or another.
Some of the views conflict with other philosophical assumptions (free will being probably the biggest one), so one might choose a compatible view so one doesn't need to challenge other beliefs.

You have not represented the views well. Eternalism does not posit that all events exist simultaneously, which means at the same time. The events all exist with equal ontology, but they have frame dependent time coordinates that are not all the same, so they're not 'simultaneous'. For instance, any time-like separated pair of events is objectively ordered 'this one, then that one'. They can not be simultaneous or ordered the other way around.

Block Time theory as distinct from eternalism? Something you move through? That sounds like a different name for moving spotlight, so perhaps I withdraw my initial comment. It's a dualistic epiphenomenal view.

Plank length is not a physical limit, only a limit of significance. If I have it right, any pair of points separated by a distance smaller than that is not meaningfully/measurably distinguishable from just the two being the same point. It doesn't mean that the two points are necessarily the same point. But I gave some QM examples that suggest a non-continuous model of reality.
— noAxioms
I have been wondering about exactly that point, and trying to work up the courage to articulate in this context. Thanks. — Ludwig V

Well my quote above is not given from authority. Planck units are just a standard of natural units. A Plank length is a small distance, but the fact that they know that distance down to at least 7 significant digits means that far smaller space units are meaningful. Still, wiki says "Since the 1950s, it has been conjectured that quantum fluctuations of the spacetime metric might make the familiar notion of distance inapplicable below the Planck length", which is similar to what I was trying to convey.

There's lots of useful stuff on the wiki Planck units page that's better expressed than me trying to paraphrase it here.

Interestingly, a unit of Planck energy is said to be the equivalent of the chemical energy contained in the fuel tank of a fairly large car. Certainly not the minimum meaningful energy. One unit of Planck force is an even larger silly number. Such is the way with natural units.

If physics requires a non-continuous model of reality, then so be it, but then it would be empirical (physical) and wouldn't affect the geometrical concepts, would it?

A more complex model for the universe does not effect a simple geometric model at all, no. The simple model simply isn't fully applicable to the reality it is supposed to describe, just like Newtonian physics isn't fully applicable to the same reality, despite the fact that they'll continue to teach it in schools.

If what happened to the question whether matter was continuous or not is anything to go by, I think that a third alternative is most likely.

Somebody still suggests that matter is continuous? I mean, that sort of went out the window a couple centuries ago.

I imagined you lot were talking about metaphysical rather than logical possibility. — fdrake

Actually, I've been asking about the distinction between those two. Nobody has really answered. A nice example (not a supertask example if possible) of something that is one but not the other would be nice.

So you’re claiming that it’s logically possible to have recited the natural numbers in descending order. That’s evidently absurd. — Michael

It may grind against your intuitions, but no logical argument against it has been presented. That you personally find it 'evidently absurd' carries no weight.
How does it start? That's easy. When the appropriate time comes, the number to be recited at that time is recited. That wasn't so hard, was it? It works for both scenarios, counting up or down.

I doubt that consciousness is computable — fishfry

what, because consciousness is not a physical process, or that physical processes cannot be simulated? You seem to be in the former camp. If that's the case, then no, it probably isn't computable.

After all if we're computations, what are the odds we'd figure that out right when we're in the age of computation?

Pretty much 1-1 odds. That's when the terminology became part of our language. You describe yourself in terms of the things you know.

We are water. The vast majority of mass would be lost (as would consciousness) if the water was taken away. Lots of pipes going here and there. It's a pretty good description for the Roman days.

Because if so, then where is the conscious mind? In the pencil? In the paper? In the air? In a neural network?

In the process.

Yes, I saw a domino logic gate on Youtube a while back.

Gawd, I spelled it 'Turning' machine. More typos.
Anyway, yes, the discussion was inspired by that. Any moron can create a domino or gate, but creating a nor gate gets tricky. Any gate can only be used once, so it's impossible to create say a flip flop, normally a trivial thing created with a pair of nor gates.

I've not seen the video, but mention of it inspired me to design a Turing machine with the technology. Can dominos be used to run a physical simulation? I think it's possible since I found not obvious roadblocks. I'm tempted to start a topic on it, but not here since it isn't a philosophy topic at all.

Perhaps it's some kind of analog computation, but that's not the same thing.

I've also programmed analog computers in school, never on the job. It's a different sort of thing, I tell ya.

ps -- I checked out the Simulation thread and from there, saw your initial post in the "What is the Simulation Hypothesis" thread, and I agree with everything you said. I especially appreciated the distinction between simulation and VR, which is something a lot of the simulation discussions miss.

Your view of consciousness is modelled by a VR. One big distinction is that a VR cannot be implemented with paper and pencil (or dominos).

I was imagining a clock that speeds up in its ticking to ape a convergent geometric series. — fdrake

OK, that would be pretty much what has been the topic of discussion this whole thread. If it completes in finite time, it's a supertask. Don't forget the inverse case where the clock starts fast and slows down to its final tick.

I think you misunderstand Zeno's paradoxes. Zeno concluded that Achilles cannot overtake the tortoise. That is explicit. — Metaphysician Undercover

Correct, but a second unstated premise must be assumed in order to draw this conclusion, since without it, one can only say that the tortoise cannot be overtaken at any particular step. That second premise might well be that supertasks cannot be completed. That premise is indeed in contradiction with the first premise and empirical observation. At least one of the three is wrong.

even though the logic proceeding from fundamental axioms proves

Fundamental axioms? None of the premises are that. They're both easily doubted.

Due to the strength of the empirical evidence, we are led toward the conclusion that the fundamental axioms concerning the continuity of space and time, and the infinite divisibility of those continuums, must be faulty.

Or the premise of supertasks being uncompletable is wrong, or that empirical evidence isn't as strong as is asserted.

Asserting that your premise of choice must be the faulty one is a mistake.

Why? The ticks per second is also going to infinity. — fdrake

The sum of an infinite set of identical finite numbers is not finite, no matter how small the number being summed. It needs to complete in finite time to be a supertask.

I don't really think it matters whether this is a supertask or not, though. It was an attempt to give an example that hits Michael's argument.

does not prove that the following supertask is metaphysically possible: — Michael

I was wondering about what is actually meant by 'metaphysically possible' or 'logically possible'. The latter is probably the same as 'mathematically possible', but I'm wondering how the former is distinct.

I notice you ignored my prior post. That itself indicates to me that you do not intent to actually consider points made against your stance. I was hoping for more confidence in it.

No. I'm talking about computability theory. — fishfry

Gotcha. No argument then. As I already pointed out, you had referenced power instead of computability: "there's no difference in computational power between parallel and serial processing." and I took it as a statement of work over time.

I brought this up in my simulation-theory topic. A simulation of Earth to a precision sufficient for consciousness can be done by pencil and paper, or by dominos falling, The latter is really interesting: set up dominos so that you get the function of a Turning machine. Not easy, but it seem that it can be done.

Whether someone regards that as a supertask or tells me I forgot about the Planck limit and so forth are different issues.

Plank length is not a physical limit, only a limit of significance. If I have it right, any pair of points separated by a distance smaller than that is not meaningfully/measurably distinguishable from just the two being the same point. It doesn't mean that the two points are necessarily the same point.
But I gave some QM examples that suggest a non-continuous model of reality.

The Zeno Wiki page doesn't mention a horse. Did I miss something? Ludwig V mentioned a horse too.

Yes. Search for 'horse' in the last 20 posts or so.

But empirical knowledge has problems like what Hume showed with the problem of induction. Because of this, empirical knowledge does not prove the supertask to be impossible. — Metaphysician Undercover

Because of this, empirical knowledge doesn't prove pretty much anything to be possible or impossible. That's why science theories are supported by evidence and not by proofs. They'd be theorems, not theories, if they were provable.

That the supertask is not completable is not denied, that it is not completable is what actually leads to the problem. In Zeno' paradox Achilles never catches the tortoise because the supertask is never completed.

I beg to differ. That simply does not follow from the description. Zeno describes a physical completable supertask, which is only as possible as the soundness of his first premise.

Achilles will pass the tortoise, and in the op 60 seconds will pass. This shows that the supertask as a fiction.

Again I differ. The supertask (if that premise is true) is not fiction. I mean, my opinion is that there isn't a physical supertask, but opinion isn't evidence, and I have no evidence (let alone proof) that it isn't a supertask.

Declaring something to be impossible is a strong claim and requires strong evidence.

That seems to me a good response, though not quite the knock-out blow one would hope for. — Ludwig V

If there was an easy knock-out blow to it, it wouldn't be a topic on philosophy/mathematical discussions.

This logical consequence can be shown when the experiment is explained more clearly:

A1. At t0 the lamp is off
A2. The button is pressed only as described by this sequence of operations: at t1/2 I press the button, at t3/4 I press the button, at t7/8 I press the button, and so on ad infinitum

Compare with:

B1. At t0 the lamp is off
B2. The button is pressed only as described by this sequence of operations: at t1/2 I press the button

The status of the lamp at t1 must be a logical consequence of the status of the lamp at t0 and the button-pressing procedure that occurs between t0 and t1 because nothing else controls the behaviour of the lamp.

If no consistent conclusion can be deduced about the lamp at t1 then there’s something wrong with your button-pressing procedure. — Michael

I see that you have an opinion, and that you are attempting to rationalize this opinion. But you leave some pretty low hanging fruit in this post, and rather than have me point them out and you denying whatever it is I post, I invite you to step into my shoes and critique the above. If your opinion was the opposite, what portions of the above argument would you put in bold and say is wrong?

I want to see if you are aware of the issues against which you are arguing.
Your response to me never seems to be along such lines. Instead of pointing out faults in my assertions or whatever, you simply ignore the argument and post yet another rewording of a counterargument, making the same mistakes (from my point of view). So show me that you at least know where I think those mistakes are being made.

The important part is in bold. If there is a problem with the button-pressing procedure, which there is in the case of A2, then this problem remains even if the button is broken and doesn't actually turn the lamp on — Michael

OK, the bold line is telling. There is something wrong with the procedure. I've pointed it out in several posts. The lamp isn't broken. That violates the mathematical definition of how the thing works. There is no physical lamp since physics cannot do what is described.

A clock ticks 1 time per second.
You start with a cake.
Every second the clock ticks, cut the cake in half.
Make the clock variable, it ticks n times a second.
The limit clock as n tends to infinity applies an infinity of divisions to the cake in 1 second. There is no final operation. — fdrake

This is not a supertask, not even as the tick rate increases arbitrarily high, because the cake (if it is continuous, which a physical one isn't) is going to take forever to consume at any clock rate.

I'm sorry I don't know about Zeno's horse — Ludwig V

Look at the context to which my "Zeno's horse" was a reply. You were talking about Ryle saying something on the order of "putting a mathematical harness on a physical horse". It's what Zeno is doing with any of his scenarios, and what almost none of the other scenarios is doing.

If you mean Thompson's lamp, quite so.

The lamp, and almost all the other examples that are not Zeno. They all seem to argue along the lines of <if impossible/self-contradictory thing is true, then contradictions result>. This is a bit like asking "If the sun suddenly didn't exist, how long would it take Earth's orbit to straighten out?"

Do I understand correctly that Thompson actually argued that supertasks are impossible?)

I don't see that. At best he showed that one example is undefined. To prove something impossible it must be shown that there is not a single valid one. To prove them physically possible, one must show only a single case (the proverbial black swan). Nobody has done either of those (not even Zeno), so we are allowed our opinions.

The physical premise of "for something to go from A to B, it must first go halfway there" is very questionable. A great example is a photon going from emitter to detector. Nothing in quantum theory says that the photon is at the halfway point at the time halfway between the emission and absorption events. The principle of counterfactual definiteness (PCD) says it is, and that principle has never been demonstrated to be the case. It is in fact not the case in mosl interpretations of quantum mechanics, including any of the ones that deny faster than light causality.

Not sure what you mean by potential cardinality. — fishfry

Pick a number, say 27. I believe it has been shown that there exists a set the cardinality of which is 27, if that's valid terminology. One could also reference aleph-26, but I'm not sure that one can prove that no sets exist with cardinalities between the ones labeled 1 through 27.

Point being that you get no increase in computational power from parallelization.

I beg to differ. A 16 processor machine can sustain a far greater work load than a single-processor machine. The Cray machines were highly parallelized (SIMD architecture) in which thousands of floating point operations were performed by every instruction. These machines were great for stuff like weather simulation.

No function is computable by a parallel process that's not already computable by a linear process.

With that I agree. But that same function can also be done by paper & pencil. You said 'powerful', a reference to how fast the work is completed, and more processors helps with that.

Coloring the steps reduces to the lamp.

I notice that any scenario with a contradiction involves invoking magic. Suppose this physically impossible thing (infinite gods, stairs requiring faster-than-light speed, lamp switches that operate without delay. No magical measurement of something nonexistent. Zeno doesn't do that. No magic invoked, and the first premise thus produces no paradox.

My Quora feed gives me a lot of cute cat pics lately. Makes me happy. Quora certainly used to be a lot better.

Oh it serves its purpose, but correct answers are not promoted above the others, and apparently a great deal of their posters don't know what they're talking about when it comes to stuff like this.

Ryle might have called it a category mistake and talked of putting a physical harness on a mathematical horse or (better, perhaps) putting a mathematical harness on a physical horse, He and many others thought that nothing further needed to be said. — Ludwig V

It is very valid to apply mathematics to physics, but it really helps then if that to which it is being applied is actual physics. Creation of a device to measure a nonexisting thing is not actual physics.

Zeno's horse is quite real. Almost none of the others are.

That's almost right, the logic is valid, but not necessarily sound. — Metaphysician Undercover

Exactly so. I have correct my post. I meant valid and wrote 'sound' in haste. A simple application of modus ponens shows the lack of soundness of Zeno's conclusion iff empirical knowledge is given any weight.

The conflicting premise which would be used to disprove this, the limitations of divisibility

The conflicting premise seemed to be a denial of the completability of a supertask. He never suggests a limit to divisibility.

↪noAxioms you seem to think the supertask is generating so fast it evades us, in fact we can meet it and persevere at the front of its generation, or even cut it all in one swift equation, — Barkon

I have no idea what that collection of words means, so while it may seem to you that I think it, I quite assure you that I don't.

√ω has no meaning in the ordinals, but I believe it does have meaning in the Surreal numbers, which I don't know much about. — fishfry

OK. I'll accept that. I do believe somebody has shown no limit to the potential cardinality of some sets.

But naturals aren't integers which aren't rationals which aren't reals which aren't complex numbers which aren't quaternions.

Missed one. :smile:

Wiki has many errors.

Ditto with SEP.

In computer science you can always linearize parallel streams, there's no difference in computational power between parallel and serial processing.

I worked a great deal of my career writing code for multiple processors operating under the same address space. It gets interesting keeping them from collisions, with say two of them trying to write different data to the same location.
Anyway, not sure what you mean by your statement. It seems on the surface to say two processors is no more powerful than one, which isn't true, but two also isn't twice as powerful.

Clearly it isn't a supertask if it is impossible to go only half the remaining distance for some intervals. If that is possible, then it must be a supertask.
— noAxioms
Ok, then since walking is commonplace, so are supertasks.

You didn't read my comment then. Ability to move is a given (an axiom, not something that can be proven). Given that, doing so is a supertask only if Zeno's premise holds, that for any starting point, one must first move halfway to the goal. I can't prove that it holds, but I can't prove that it doesn't hold either.

Yes. Although the rationals don't represent any ordinal. The ordinals only apply to well-ordered sets.

OK. Yet another thing I didn't know.

I defined the terminal lamp state as a plate of spaghetti.

Yes, the PoS solution.

unlike the lamp, there IS a naturally preferred solution to the staircase. If the walker is on each step at each time, then defining the walker to be present at the bottom of the stairs preserves the continuity of the path. So the staircase (if I even understood the problem, which I may not have) at least has a natural terminating state.

Does 'bottom of the stairs' imply a bottom step? If every other step was black and white, what color is the bottom step? PoS, I know. Same problem from where I stand.

No idea. Found a physics.SE thread.

I'll look at that. I have all the respect for the PSE guys, who blow everybody else away. Quora stands somewhat at the opposite end of that spectrum.

It [completing without a last step] means that is isn't a finite sequence of operations.
— noAxioms

No, it doesn't. Saying that it is an infinite sequence of operations means that it isn't a finite sequence of operations. — Michael

Finite means bounded. That means a finite sequence of steps that has a first and last step. An infinite sequence means not (a finite sequence of steps that has a first and last step). It being called 'infinite' literally means that the last step you keep referencing doesn't exist.

I see you have Barkon joining your ranks. I hope you find the company good.

What does it mean for every operation to occur without some final operation occurring? — Michael

It means that is isn't a finite sequence of operations. How is it a contradiction that there isn't a final natural number? Instead of just asserting it, show it.

@Barkon also seems to be running on his intuitions and makes unjustified assertions.
If I'm wrong, don't just tell me; show me where.
If Michael is wrong, don't just tell him; show him where.

How can a sequence of operations in which each occurs after the other complete without there being a final operation? — Michael

By definition, the sequence completes by having every operation occurring before some finite time. To demonstrate otherwise, one must find a remaining operation which necessarily is not completed at that time.

That there must be a final step in such a sequence not only does not follow from the description of such a supertask, it in fact directly contradicts the description of the supertask.

To demonstrate the impossibility of Zeno's physical supertask, one must attack the premise, not the logic. The logic is valid, at least until he additionally posits the impossibility of the first premise, but that only gives rise to a direct contradiction, not a paradox.

X is a true fact of motion. X is is a false fact of motion. Therefore either motion is impossible, or at least one of the premises is wrong.

strictly with respect to order, they are two different representations of the same ordered set. — fishfry

Agree.

Transfinite ordinal numbers are numbers.

Are they? Does √ω have meaning? It does for numbers. It's a serious question. I am no expert on how transfinite ordinal numbers are treated. It seems like a different species, like having a set {1, 2, 3, ... , green} which is also a valid set, and countable.

Yes, ordered set. I have been casually using the curly braces, but you are absolutely correct. {1/2, 3/4, 7/8, ..., 1} has no order, I could stick the 1 in the middle or at the beginning and it would be the same set, but I'd lose the order that I consider important.

Ordering irrelevant. The set supposedly needs to be countable, and it is. Michael's definition of supertask came from wiki, and that definition says it is countable, else it's a hypertask. The SEP definition of supertask omits the 'countable' part and seemingly groups the two categories under one word.

The definition also includes 'sequential', meaning parallel execution of multiple steps is not allowed.

Yes ok but then ... how is walking across the room by first traversing 1/2, then half of the remaining half, etc., not a supertask?

Clearly it isn't a supertask if it is impossible to go only half the remaining distance for some intervals. If that is possible, then it must be a supertask.

It violates thebijunction
— noAxioms

I take that back. It doesn't violate the bijection. And I spelled it wrong too. So many errors.

Note that I no longer have an order-preserving bijection.

That's fine. The rational numbers are both ordered and countable, but they cannot be counted in order.

Ah yes, why am I doing all this?

It solves the lamp problem. The lamp state is a function on <1/2, 3/4, 7/8, ..., 1> defined as "on" at 1/2, "off" at 3/4, "on" at 7/8, and so forth.

But now we see (more clearly, IMO) that the state at 1 is simply undefined. The statement of the problem defines the lamp state at each element of the sequence; but does NOT define the state at the limit.

Sounds like the lamp problem is unsolved. It is still 'undefined'.

Another note: The paradox of the gods that I occasionally bring up is fun to ponder, but it isn't a supertask since it cannot be completed (or even started). Progress is impossible. Ditto with the grim reaper 'paradox' where I die immediately and cannot complete the task.

Note that the staircase is different. The walker is on step 1, on step 2, etc. So the natural, continuous way of completing the sequence is to say that the walker is at the bottom of the stairs.

There is no bottom, and the OP did not suggest a bottom step. He is done, and no stairs are observable. It's mathematical only, but framed with a physical sounding analogy, which makes it fall apart.
Your ω might help with the stairs. The guy is at 'the bottom' and there is but the one step there, labeled ω. No steps attached to it, but step on that one step and up you go, at some small finite numbered step after any arbitrarily small time.

Unless the answer is that we satisfy Zeno and execute a supertask every time we walk across the room. But Michael objects to that, for reasons I don't yet understand.

His assertion isn't justified, I agree.

Some speculative physicists (at least one, I believe) think the world is a large finite grid

So much for the postulates of relativity then. I kind of thought we demolished that idea with some simple examples. It seems to be a 'finite automata' model, and the first postulate of SR is really hard (impossbile) to implement with such a model, so a whole new theory is needed to explain pretty much everything if you're going to posit something like that. I haven't read it of course, so any criticism I voice is a strawman at best.

The chessboard universe sounds very classical, and it's been proven that physics is not classical, so I wonder how this model you speak of gets around that.

Well ok, then why don't I complete a supertask when I walk across the room, first going halfway, etc.? Can you distinguish this case from your definition?
— fishfry

If supertasks are impossible and motion is possible then motion isn't a supertask. — Michael

This evaded the question ask. Sure, we all agree that if supertasks are impossible, then supertasks are impossible. He asked how you justify the impossibility of a supertask. All your arguments seem to hinge on a variant that there isn't a largest natural number.

By definition supertasks are non-terminating processes — Michael

The wiki definition you gave made no mention of 'terminate'. If you mean that it doesn't complete, it by definition does in a finite time. If you mean that it has no terminal step, then you're making the mistake I identify just above since the definition does not require one.

Tasks are performed ad infinitum. I never stop counting. — Michael

You also wield the term 'ad infinitum', which typically means 'going on forever', which also violates the definition which explicitly requires a finite time to the task You very much do stop counting at time 1. There is at that time not another number, so by counterexample, your assertion that you will never stop counting is false.

They are not premises. (3) isn't intended to follow from (1) and (2). — Michael

Right you are.
They are three options, and the premise (the one and only and false one) is that one of the three options is very likely to be true. In fact, all three as you stated them are unlikely and a 4th option is the true one: There is neither capability nor desire to run sims of more conscious humans than there are real humans.

As for 1, his assignment of low probabiltiy to that is due to becoming extinct before it happens, not to it not being plausibly possible. Discussion of item 2 seems to suggest that it is for some reason, something that a wealthy person would want to do. I have no idea why. I guess it implies that despite this arbitrarily advanced technology, it's still costly to use it.

Yes, I agree that nowhere in the paper (except an impication in the title) does he conclude that the third option is the most likely. He's done talk shows and such, and there's very much an argument for its likelihood, but maybe such assertions are necessary to get him on the paying talk show.