I dunno OLP heads, "is" sure crops up in a lot of language games with different grammars. Almost as if there are different uses of it!

Violent Faculties by Charlene Elsby

Sadistic horror written by a philosophy PhD. The plot is a rogue philosophy prof literalising thought experiments on willing or coerced subjects. Think it'd give some of you lot a chuckle.

They're clearly being confused by maths. They think that because a geometric series of time intervals can have a finite sum and because this geometric series has the same cardinality as the natural numbers then it is possible to recite the natural numbers in finite time. Their conclusion is a non sequitur, and this is obvious when we consider the case of reciting the natural numbers (or any infinite sequence) in reverse. — Michael

I imagined you were arguing toward the claim that anything which has no first event is not physically possible. Which is a bit different from the geometric series angle. Which shows that there are logical possibles which have no first event. The sticking point between you and us series heads seems to me that you've been arguing on the basis of "no first event" blocking logical possibility, which would then block physical or metaphysical possibility. Which is why I intervened, because while I agree with your argument strategy, the means you were arguing for it were imprecise enough to admit the geometric series counterexample. I do think your points can be steelmanned though.

You might come up with a mathematical model for "recitation of first element", which maps a series to its minimum or maximum. Since the series has a minimum, you can do that. It has no maximum, so you can't. It's the same principle as asking someone to count backwards from infinity. And then it's true, it's not logically possible to "recite" backwards from infinity, or "recite" the maximum of an increasing geometric series.

Going back to the first page of the thread, such a "recitation" for the state of Thompson's lamp, or just isolating the "state", could be construed by taking a time period and associating it with the states the lamp takes in that time period in order. If Thompson's lamp has states in a time period, they'll be picked out by that. However, the function which generates the values of Thompson's lamp has the property that for every time period X, there exists a time period Y such that if max( Y )>max( X ) then Y contains at least two states (on or off). You get those by going further toward the completion time. That property implies there is simply no "state" of the lamp at limit of 2 minutes. So it having a state is logically impossible.

What makes Thompson's lamp a paradox, then, is a physical or metaphysical intuition about the concept of the state of the lamp. There needs to be a beginning to the process, and it needs a unique isolable end state. Both the geometric series and Thompson's lamp have no unique isolable end state.

That will then bottom out in an inquiry about whether there are physical or metaphysical possibles which have non-unique and non-isolable end states.

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.. — noAxioms

I'm pretty sure that one comes down to being able to split the pieces up into pieces that aren't measurable - IE can't be assigned a size - in a clever way, then applying some cool transformation to them that blow them back up into the sphere. But that's by the by.

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. — noAxioms

I think that's a species of metaphysical possibility - a different physics. What would distinguish that from logical possibility, in my book, is that there are simply more ways of being noncontradictory than being unable to exist in our universe. Like flibbertygibbets. And nonmeasurable sets. And, maybe, abstract categories.

I don't think it impossible for a geometric series to complete. — Michael

Good! Then it's logically possible for it to. An infinite number of things can complete without blowing up logic.

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. — noAxioms

I don't have a particularly clear cut example to distinguish the two. And I don't know if the concept of logical possibility survives the existence of nonclassical logics. But what I envision for logical possibilities are things which don't by themselves, and with no other contextual information, entail a contradiction. Any possible fact is logically possible.

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).

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.

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 hear a use of a metaphysical or physical context of events, speech and recitation which just isn't there in the definition of mathematical terms. And in that regard @Michael's response addresses physical or metaphysical possibility, rather than logical possibility.

The only reason I intervened is to pedantically point out the distinction, and that Michael let it slip for at least one post.

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

Nah. That's an appeal to metaphysical or physical impossibility. Not logical impossibility!

The sequence {1/2n} for n=1 to infinity has a finite sum, 1. That's numbers and an infinite set. So yes, geometric sequences have a model in set theory. They also have a finite sum, no last operation, and contain an infinity of operations. You can think of the partial sum, up to the nth term, as the total time elapsed on clock whose ticks last 1/2n. The limit construction exists without contradiction. The reason being that the sequence gets arbitrarily close to its greatest lower bound (0). And there is no smallest element, since the greatest lower bound isn't in the set.

How can a sequence of operations in which each operation is performed only after the previous operation is performed complete without there being a final operation? — Michael

So there is no final operation, there is an infinite sequence of operations, and it completes in a finite time. Since the completion time is just the limit of the partial sums.

There's your model. Logically possible. I leave now.

OK, that would be pretty much what has been the topic of discussion this whole thread. — noAxioms

I imagined you lot were talking about metaphysical rather than logical possibility. @Michael made a comment to the effect that such a construction was logically impossible. Which would be odd, seeing as such an object has a model in set theory. Even if it's not physically or metaphysically possible. All I wanted to add.

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. — noAxioms

Aye that is true. I wrote wrong. I was imagining a clock that speeds up in its ticking to ape a convergent geometric series.

The fact that there is a bijection between the series of time intervals and the series of natural numbers and that the sum of the series of time intervals is 60 does not prove that the following supertask is metaphysically possible: — Michael

The lamp starts off. Every time the clock ticks a lamp turns from off to on or from on to off as applicable. Thomson's lamp shows that this leads to a logical inconsistency. — Michael

Might show it's logically possible tho.

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. — noAxioms

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

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.

The lamp starts off. Every time the clock ticks a lamp turns from off to on or from on to off as applicable. Thomson's lamp shows that this leads to a logical inconsistency. — Michael

By providing a standard mathematical object which is infinite, has no final element, tends to an end state, and has an infinite number of occurrences ("steps"), but occurs in finite time.

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

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.

There's nothing logically inconsistent in this, it's just not "physical".

@Banno @J

(ii) quantifiers cannot vary their meaning intensionally without collapsing into logical pluralism;

That is what you see in practice though. There are no modal operators in propositional logic. But both modal and propositional logic are great. Their semantics also differ considerably. When you write the possibility and necessity symbols in a modal logic, you quantify over possible worlds. When you write them in a quantified modal logic, you quantify over worlds, and there's also quantification within worlds in the usual logic way.

Those quantifiers are introduced differently, and as the paper "Quantifier Variance Dissolved" notes that provides a strong argument for a form quantifier variance without a reduction of quantifier meaning to underlying entity type it quantifies over, and without committing yourself to the claim that there's a whole bunch of equally correct logics for the purposes of ontology.

It's gonna be hard to write them down.

Though something like the act of marrying two people is done with language, rather than expressed by it. Though in a less restricted sense of expression and meaning, perhaps the meaning of "I do" is the act of agreement. And in that sense "I do" expresses an agreement to the contract of marriage. But that says nothing more than an agreement was made.

Perhaps then, the use of language expresses nothing at all. It simply does. Transforming situations to other situations. Expression would then be a metaphor for an element of that transformation. A folk tale for coordinating our actions before, during and after our actions transform us.

Naw. I close now.

A not so gentle reminder to keep the distinction between zionists and Jews, and pro-palestinian/anti-zionist people and anti semites in your head at all times. The same goes for Hamas and palestinian people+Hamas and the Islamic. If you equivocate, you just end up calling each other racist for no reason. Stop it. That goes for you @BitconnectCarlos as well as @Lionino, and @Benkei should have known better.

(Gallup pole from 2023) Americans say they read an average of 12.6 books during the past year, a smaller number than Gallup has measured in any prior survey dating back to 1990. U.S. adults are reading roughly two or three fewer books per year than they did between 2001 and 2016.

My completely unreasonable hunch is that this poll was answered by book readers rather than the general populace. 1 book a month is a lot for almost everyone I know - including non-dense fiction readers!

I fear there's long term effects on our societies with this. What do people think about this? — ssu

My second completely unreasonable hunch is that the decline of book reading is a symptom rather than cause of declining levels of education.

eliminative materialism. — Wayfarer

Dennett's not an eliminativist though. He's a critic of it.

One perspective (Dennett, 1987) is that propositional attitudes are actually dispositional states that we use to adopt a certain heuristic stance toward rational agents. According to this view, our talk about mental states should be interpreted as talk about abstracta that, although real, are not candidates for straightforward reduction or elimination as the result of cognitive science research. Moreover, since beliefs and other mental states are used for so many things besides the explanation of human behavior, it is far from clear that our explanatory theories about inner workings of the mind/brain have much relevance for their actual status.

From SEP. He isn't even an eliminativist toward "experience". Just thinks it's thought of badly.

Oh yes absolutely. I have in mind Austin's comment that while word use should be the first word on a topic, it need not be the final one!

Thanks for the reference. I'd highlight, in another context, that there's room for revising an understanding in ordinary language for some purpose. Like "know" could mean something different in the context of a mathematical proof, a scientific experiment, or a history book. But it's not particularly relevant. Even if those understandings may even be better in context than the pretheoretical one which we all engage with.

Well that paper is very similar to the debate we're having.

I suppose it's also why people have invited you to reconsider the kind of things that can count as direct realism!

Well we're kinda screwed if we can't agree what we're disagreeing about.

And then, of course, there are direct realists who view experience/perception as the actualization of a capacity that persons (or animals) have to grasp the affordances of their world. Brains merely are organs that enable such capacities. — Pierre-Normand

Yes, that's a species of externalism isn't it?

Edit: removing some laziness in the question. There's the adage that externalism means "meaning ain't just in the head", ecological perception like Gibson sees signs and capacities for acting in nature. Environmental objects themselves are seen as sites of perceptual interaction, which imbues interactions with them with a dynamic/semantic content.

And this would be wrong. — Lionino

Eh, a perception is still an event in the world. Like your body adjusting under a load is proprioception.

I think that's one of the central axes this debate is happening on. Direct realists in thread seem to see experience/perception as a relationship between the brain and the world that takes place in the world. @Michael seems to see experience/perception as a relationship between the brain and the world that takes place in the brain.

Edit: so we've got externalism+directness+action vs internalism+indirectness+representation.

No. Experience exists within the brain (either reducible to its activity or as some supervenient phenomenon), whereas proximal stimuli exist outside the brain. So neither proximal stimuli nor distal objects are constituents of experience. — Michael

I think I understand. So for you, this process goes like:

distal object -> proximal stimulus -> interpretation -> mental phenomenon

and/or

distal object -> proximal stimulus -> interpretation -> experience

and for you, "interpretation" and "mental phenomenon", as steps of the process, are what perception is?

Mental phenomena; colours (inc. brightness), shapes, orientation. — Michael

Proximal stimuli?

Because naive and indirect realists mean the same thing by "visual experience" but disagree on its constituents and so disagree on whether or not we have direct knowledge of distal objects and their properties. — Michael

What are the constituents of visual experience?

Nothing Google couldn't tell you quicker than us.

The proximal cause is the entity that stimulates the sense receptors. With sight it's light, with hearing it's sound, with smell it's odour molecules in the air, and with touch and taste it's the distal object itself. — Michael

I see what you mean. I think you need to ask "which" sound or "which" light though. The light which serves as the stimulus for seeing a brown table is the light reflected off of that brown table. In that regard, the proximate cause of you seeing a brown table (in a case of veridical perception) is the reflection of that light from that brown table. In that regard, the behaviour of the distal object (the brown table) in its environment acts as the proximal cause of the perception event.

Does that seem suitable to you?

I am not claiming that the table is the "proximal stimulus" of the perceptual event, since that's not right, I'm claiming that the reflective properties of the table - IE, the properties of the distal object - are the proximal cause of the perceptual event which we'd call seeing the distal object. IE, the properties of the brown table proximately cause us to see it.

If you're looking at a brown table "out in the wild", what you see isn't the proximal stimulus either. Since there isn't just one, and it isn't unique. "The" proximal stimulus is instead a sprawling set of retinal images integrated with other senses through a process of interpretation. As part of sight (as part of perception broader), those retinal images are filtered and stabilised - IE interpreted - into time stable perceptual features. Vision doesn't happen all at once.

In that respect, when we're speaking of "proximal stimuli", we're not speaking of the familiar objects at hand. Proximal stimuli for vision are horrifying chaotic things. Dancing lights, colour patches with no depth or thickness, unpeopled, unfurnished, textureless and silent.

A tall woman standing to the right of my table, near the light illuminating it, reduced the incident light onto one portion of the table in my peripheral vision quite substantially. She then left. I saw the table as the same colour and intensity throughout despite her changing how light was reflected from it. I saw no changes in my proximal stimulus since those proximal stimuli are how I detect vision related environmental changes. I saw no changes in the distal object as my interpretation of it was not influenced by irrelevant detail.

There isn't a "proximal stimulus" of the brown table - what there is is a sequence of retinal images which are interpreted as part of sight into a brown table. There is however the distal object, which is the proximal cause of the table related aspects of all our proximal stimuli in veridical perception - and that is what we perceive.

Well, certainly not when it comes to sight where the proximal stimulus is the light. In the case of touch and taste they'd agree. — Michael

Thanks.

Why do you think that the proximate cause for touch and taste is the distal object but not for sight? How about hearing? Kinaesthesis?

There's a distinction between a distal object being a constituent of experience and being a cause of experience. Indirect realists accept that distal objects are a cause of experience but deny that they are a constituent of experience. — Michael

Do you think that indirect realists can accept that distal objects are the proximate cause of experience? That is the sense I meant.

As I see it indirect realism is nothing more than the rejection of naive realism, with naive realism claiming that distal objects are literal constituents of experience, entailing such things as the naive theory of colour. — Michael

You mean like direct realism = the apple is distal object is numerically identical to the apple percept?

I have knowledge of percepts but I don't have knowledge of the proximal stimulus or distal object. — Michael

Right so let's go back to this. I'm trying to find something we can agree on a framing of so that we can start having a productive chat.

I agree that we have knowledge of percepts. To me that is distinct from forming a percept - ie perceiving. So to me, forming knowledge of percepts is distinct from the problem of whether perception is direct or not.

For reference I'd like to use SEP's characterisation of direct realism.

This has a few claims. We've touched on some of them.

• Ordinary Objects: perceptual experiences are directly of ordinary mind-independent objects.
• Presentation: perceptual experiences are direct perceptual presentations of their objects.
• Direct Realist Character: the phenomenal character of experience is determined, at least partly, by the direct presentation of ordinary objects.
• Common Kind Claim: veridical, illusory, and hallucinatory experiences (as) of an F are fundamentally the same; they form a common kind.

I'd agree -with some caveats- to ordinary objects, presentation, direct realist character, but reject the common kind claim (I imagine I'm some kind of disjunctivist). My caveats would be:

• Ordinary Objects Caveat: perceptual experiences are directly of ordinary mind-independent objects in the sense that mind-independent objects reliably cause percept properties to hold which intersubjectively count as each other. By this I don't mean that your red is identical to my red, but that if we both see the same apple, we can come to agree on whether it's red or not. For the dress, we can come to agree that it's either black and blue or gold and white.
• Presentation caveat: perceptual experiences are direct perceptual presentations of their objects in the sense that perceptual experiences are perceptions/percepts and that causes of percept properties are tightly constrained by distal object properties. Like reflectance spectra tightly constraining seen colour.
  
• Direct Realist Character: the phenomenal character of experience is determined, at least partly, by the direct presentation of ordinary objects. No caveats here.

I'd reject the common kind claim, for me illusions and hallucinations don't seem like an instances of perception. But for different reasons. Hallucinations don't have an in principle manipulable distal object or set of environmental causes, and thus aren't subject to the causal constraints of active perception. Illusions my jury is still out on.

For me, whether something seems to be X to me is not paradigmatic/definitive that I have perceived X. For example, I could have misperceived X, or what my perceptions seem to me to be (upon reflection, memory, the next moment...) may not be what they are. The paradigmatic instance of perception for me, then, is a veridical perception in an active account of perception.

I imagine, though please correct me if I'm wrong @Pierre-Normand, that my ordinary objects caveat is similar to @Pierre-Normand's reference to Evans'. Though I come at it from the belief that there's good evidence perception - as well as its character - is socially mediated.

I'm finding it hard to see how the posts you're making are related, which probably means we have very different presuppositions and ways of thinking about the topic.

So if I'm hearing you right, you believe that knowledge is only of percepts, and thus access to the world is indirect?

Having a rational awareness/understanding of it. — Michael

Right, so for you "access" is something like introspective awareness?

I have access to colours and pain and smells and tastes. These are all percepts. — Michael

Describe what you see that access as, please?

We have access to percepts. Percepts are often the consequence of the body responding to some proximal stimulus. The proximal stimulus often originates from some distal object. — Michael

Mmm... You don't have "access" to a percept. A percept is identical with either the whole, or a part of, the conceptual-perceptual state of an organism at a given time. That's a numerical/definitional identity, rather than an equivalence. Like the percept is not what perception or experience is of, the percept is an instance of perception. The taste percept of my coffee is the same as how I taste it in my tasting event.

The distinction there is between saying that a percept is an instance of perception vs saying that a percept is what perception acts upon.