The idea of randomness kind of snuck into this discussion. It's not something I've thought enough about to be comfortable with my understanding. Your post is really helpful. I'm going to keep it to use as a reference in the future. I'll quote it to pound other posters into submission.

Thanks.

I don't see a difference between an outcome between two billiard balls colliding and the outcome between your finger colliding with a side of a coin. They are both predictable in the same way - by knowing the motion and force applied to all particles involved. — Harry Hindu

As I discussed previously - I'm not talking about flipping a coin and trying to predict the outcome. I'm talking about flipping the coin numerous times and predicting the exact sequence of heads and tails.

Like I said before: you are arguing for solipsism. — Harry Hindu

Maybe it would be solipsism if I were to write "Only in the sense everything only exists in my mind as imaginings", but that's not what I wrote or meant.

The way I understand it the concept of determinism is the idea that all events have physical causes which determine them 100 percent. QM of course denies this, and claims that there is a genuinely random (in the sense of not 100 percent causally determined) element in physical events. The idea of indeterminism is that at "bottom" physical events are truly random (uncaused) but that due to their large-scale probabilistic nature they average out to produce macroscopic events which seem to us to be 100 percent causally determined, I am very much open to being corrected on this, since my understanding is by no means anything approaching expert level. — Janus

I don't want to get too far from the definitions I established in the OP. The substance of the position I have presented is that I don't think it is useful to apply the concept of determinism as defined there. I have presented reasons for taking that position. This seems to be consistent with the position you've described. I agree that the system you describe which is only statistically predictable does not meet the standards for determinism presented in the OP.

As I said in the post you quoted, it is not clear to me that "random" and "uncaused" mean the same thing. One way or the other, it is not particularly relevant to the substance of my position.

To answer that question, I think it's useful to consider a simple system and how it would be represented. — Andrew M

In the OP and subsequent posts, I laid out specific meanings for "determinism" and "predictability" and the kinds of situations to which I think they apply. You seem to be using different definitions than I did.

Not ‘always’, not by a long stretch. It is very much characteristic of modern science, post Galileo-Newton-Descartes. — Wayfarer

An interesting discussion of Armstrong's work, but definitely outside limits of my experience. Maybe science hasn't always claimed to see the world from a God's eye view, but that's certainly the way I learned it. It seems to me that belief in objective reality existing beyond what we perceive requires that there be a God watching from the outside.

Be that as it may, I don't see how it changes the substance of my argument one way or the other.

I guess what I'm gesturing towards is why should we care about the perspective of God on a system when God's external to it?
— fdrake

It is incorrect to say that God is ‘external’ to the Universe. God is understood as transcendent-yet-immanent - beyond and also within. — Wayfarer

Seems to me that science has always claimed to see the world from a God's eye view, from the outside, whether or not it was expected a God was there to view it.

If we take "random" to refer to processes which are not causally determined, then, under that definition at least, there can be no randomness in a deterministic system. — Janus

Random - Of or characterizing a process of selection in which each item of a set has an equal probability of being chosen.

I don't see why that implies a lack of causation.

The "wheel-spinning" seems to be generated by the unacknowledged incompatibility of people's basic assumptions or definitions. If we can agree on basic premises and definitions, then there might be a decent chance that consensus can be achieved. — Janus

Agreed.

Can you give an example? — Harry Hindu

• "Empirical" predictability - billiard balls.
• Probabilistic predictability - coin flips

Probabilities only exist in the human mind as imaginings. — Harry Hindu

Only in the sense everything only exists in the human mind as imaginings.

Dont know. Some say science as we know it was born in the age of mechanism. As we graduate from that age, there is fear that letting go of a naturalistic anchor will open the door to rampant superstition and trance dancing.

Science could probably use some help from the part of philosophy that isn't just a cheerleader for a mechanistic perspective. — frank

Whether or not we are leaving "the age of mechanism" I don't think there's any reason to throw out the scientific baby with the bathwater. Or is it the baby with the scientific bathwater?

Quantum Mechanics' probabilistic outputs are used to build many great devices that work. — PoeticUniverse

True, but I don't see how it's relevant to the discussion.

Science (which means knowledge), will fall apart when societies withdraw support. That could happen for a number of reasons. — frank

That's not what I meant. I was trying to say that I don't think science needs determinism as defined in the OP conceptually in order continue successfully.

Free will and determinism get discussed frequently here on the forum. I don't think I've ever seen the issues laid out better and more clearly than you have here. I have lots of problems with the concepts of determinism and free will. I won't spend much time with those here. I do have a couple of thoughts.

First, and this is a theme you will hear from me over and over if you hang around the forum, determinism and free will are metaphysical and epistemological issues. As such, they are neither true nor false. They are useful or not useful in specific situations for specific purposes.

Second, there is an active thread on the post right now examining whether causal determinism is a useful, meaningful concept - "Determinism vs. Predictability."

OP Part 1

There is a group of issues that I’ve been wrestling with lately. They are ones that come up a lot on the Forum. Specific issues include determinism, predictability, probability, reductionism, emergence, free-will, causation, chaos theory. I don’t want to retread all the recent threads, so I’ll focus on a fairly specific issue. How is determinism different from predictability. — T Clark

I come down on the "no" side.

I won't say anything else to distract you from the direction you are leading the thread.

I don't think there is any [knowledge that vouchsafes causal determinism]. The assumption that all causes are knowable has historically been a part if the methodology of science. — frank

I agree with both statements.

At this point, it's also common sense. Doesn't mean it's true, but that's the foundation of causal determinism. — frank

Causal determinism is the concept that is being examined in this thread. Do you think science will fall apart without it? I don't.

I was addressing fdrake's question. Do you want me to explain my response? — frank

I went back and checked to make sure I understood what you were responding to. I think I did. Yes, a bit more detail would be helpful.

Here's what you wrote:

It's just folk wisdom that the mead you're drinking isn't going to turn into petroleum on its way down your throat without a knowable explanation.

How is our confidence in that justified? Opinions vary, but I don't think anyone believes it's dependent on somebody knowing something. — frank

I don't see how our confidence that mead won't spontaneously turn into petroleum has anything to do with determinism as we are discussing it.

Thanks for the clarification. I think I understand what you're trying to say and I agree up to a point. I guess it all comes back to

why should we care about the perspective of God on a system when God's external to it? — fdrake

The substance of my position is, if I don't believe there is an omniscient God watching and keeping track of everything all the time, and, if I believe it is not humanly possible to empirically predict any but the simplest systems, then saying the world is determined is not useful or even meaningful.

On the other hand, if I do believe in such a God, I think I would accept the case for determinism.

I guess what I'm gesturing towards is why should we care about the perspective of God on a system when God's external to it? It's a question of how structures are internalised to systems, rather than abstracting away from the details of all of them. So in my question to frank, "who's doing the knowing?", who does the knowing that vouchsafes this kind of determinism? It can't be located within a functionally bounded system - one which has demarcated modes of operation, it can only be the totality of all things viewed from the perspective of that infinite intellect. — fdrake

I think I understand what you're saying and I think I agree with you. Could you clarify a bit for someone barely literate in probability and statistics. Terms I could use help with - "structures are internalized;" "functionally bounded system;" and "demarcated modes of operation."

It's just folk wisdom that the mead you're drinking isn't going to turn into petroleum on its way down your throat without a knowable explanation.

How is our confidence in that justified? Opinions vary, but I don't think anyone believes it's dependent on somebody knowing something. — frank

You're oversimplifying and you're stepping outside the bounds of the specific definitions of "determinism" used in the OP which, as I said, are:

* A system is deterministic just in case the state of the system at one time fixes the state of the system at all future times. A system is indeterministic just in case it is not deterministic.

* Causal determinism is, roughly speaking, the idea that every event is necessitated by antecedent events and conditions together with the laws of nature.

* Determinism is the understanding that all events, including moral choices, are completely determined by previously existing causes. — T Clark

It seems to me that if you are making the case that something is the case because something else is the case, then you are making the case for determinism.

If something is completely outside the scope of human possibility and that makes it not possible in theory, and that makes the case that there isn't determinism, then you just made the case for determinism. — Harry Hindu

Two problems with this. 1) I'm talking about physical determinism, you're talking about logical determinism. Not the same thing at all. 2) I've made it clear that I'm talking about complex systems. I used an example, billiard balls, where a case can be made for predictability and determinism. You don't have to go much up the ladder of complexity before direct empirical predictability is lost and we are left to deal with probabilities. I'm using the words "direct" and "empirical" to mean predictability made possible by actually tracking the positions of particles and calculating future conditions. I'm not sure if those are the right words to use.

What exactly is outside the scope of human possibility? How would we know such a thing? — Harry Hindu

Good point. I've tried to make the case that, in all but the simplest systems, empirical predictability is not humanly possible. If I flip a coin 1,000 times, there are 2^1,000 possible combinations of results, each with equal probability. That''s about 1 x 10^300. Web says there are about 1 x 10^80 atoms in the visible universe. That's what I mean by "outside the scope of human possibility."

...according to the 'relative state formulation' of Hugh Everett, which, however, requires that the universe 'branches' every time an observation is taken. — Wayfarer

Again, my only point in this regard is that some believe QM is deterministic. I have no position on any of those arguments. My position is that since atomic events are not predictable under either quantum or classical mechanics, it makes sense to consider them non-deterministic. That is the intended substance of this thread.

As I understand, in accordance with the most common interpretations, the epistemological question is "What do we know and how do we know it?", and the metaphysical question is "What is there, and is it independent of our perceiving/knowing it?".

Of course, we can have one view or the other regarding both of these questions, and there is no question of "proof" as you have agreed. Is there any truth in these matters? — Janus

Agreed.

Is there any truth in these matters? If so, is the truth ultimately a matter of consensus, as pragmatism would have it? Or is it a matter of mere personal preference; what works for me or you? Is it a matter of plausibility, and if it is, how do we derive a standard of plausibility that is not itself a matter of mere preference or consensus? — Janus

Just to be clear, you are referring to metaphysical and epistemological truths, is that correct? If so, then yes, it's a matter of preference or consensus. If we're going to try to work something out together, we have to come to an agreement on these issues, which provide the underlying rules of the game. Otherwise, we'll just spin our wheels, as so often happens on the forum.

Wait - I like this one better.

But it does, T. Clark. It's not that far from what you're saying about the impossibility of being able to know all of the factors that collectively bring about an outcome ruling out the possibility of Laplace's Daemon. — Wayfarer

I think I agree with your interpretation but, again, it doesn't have any impact on my position. It's just another example of the case I am trying to make - if it ain't predictable, it ain't deterministic.

So it's not as if the all-seeing mind could predict how those entities are going to act in advance, as the act of perceiving them is implicated in the outcome. So they're in some sense un-knowable in principle; not simply not perceived. — Wayfarer

I don't think either you or I know exactly what God can and cannot do.

And that, of course, is one of the principle tenets of the Copenhagen interpretation of physics, of which Werner Heisenberg was one of the chief proponents. It undermines determinism. (Actually I have just learned that if you begin to search Copenhagen interpretation and det.... that google remembers the query and fills in the last word - which tells you something!) — Wayfarer

Here's what the Stanford Encyclopedia of Philosophy says about QM being deterministic:

So goes the story; but like much popular wisdom, it is partly mistaken and/or misleading. Ironically, quantum mechanics is one of the best prospects for a genuinely deterministic theory in modern times! Everything hinges on what interpretational and philosophical decisions one adopts. The fundamental law at the heart of non-relativistic QM is the Schrödinger equation. The evolution of a wavefunction describing a physical system under this equation is normally taken to be perfectly deterministic. If one adopts an interpretation of QM according to which that's it—i.e., nothing ever interrupts Schrödinger evolution, and the wavefunctions governed by the equation tell the complete physical story—then quantum mechanics is a perfectly deterministic theory. There are several interpretations that physicists and philosophers have given of QM which go this way.

I'm not taking a position on this. I'm only using it as evidence that not everyone agrees that QM undermines determinism. In terms of my argument, whether or not other people say it is deterministic, I say it's not because events at the atomic level are not predictable under either classical or quantum mechanics.

Think more simply. When something is ‘determined’ it is known, and when something is predicted it is ‘guessed’ based of determined knowledge (educated guess).

People playing at philosophy will always try and put their own special spin on it to make themselves feel validated.

As for “ontology” and “epistemology”, I agree. They are the same thing and it is merely a convenient demarcation of speech - the underlying game of philosophy where the physicist doesn’t much bother themselves with such - to be frank - tail chasing drivel (and nor do philosophers of any substance). — I like sushi

Suivita is a horse?

No listing on the web for nostervita.

I think the 'uncertainty principle' slays LaPlace's daemon. It's directly relevant to the issue. — Wayfarer

I didn't say it wasn't relevant, I said that, as I understand it, QM is considered deterministic. I just went and looked on the web. Apparently that is not completely true - some say it am and some say it ain't. However we come down, I don't think it has any impact on my position.

Is it merely a matter of fame? Does something become quintessential once it crosses over a certain threshold of saturation? What distinguishes something from being quintessential rather than atypical? — thewonder

It would be helpful if you defined what you mean by quintessential rather than just throwing it out there without explanation.

In any case the truth of any philosophical position can never be proven. — Janus

I've said this several times previously in this thread - this is a metaphysical/epistemological issue. There is no proving required. It's a question of usefulness, meaningfulness, value. What is the value of the "realist" approach in this instance. What value is there in talking about something that we can think about happening but which can never actually happen. What does it contribute to knowledge, wisdom, effective action. That's probably a pragmatist's question.

50/50 is an assessment of a formal system, not the outcome of a unique coin toss.

Maybe it would help if we considered an unbalanced object. It has a 97% chance of coming up heads. What does 97%/3% tell you about a unique toss? — frank

It tells me that, if I bet $1.00 on the fair coin, the expected value of the bet for me is $1.00. If I bet on the unfair coin and I call heads, the expected value is $1.94.

(1) If you have a complete specification of a system at some time t, then it is specified for all times before t and after t. Positions, momenta, orientations, that kind of thing.

(2) The specification procedure for all preceding and following states can be obtained by 'submitting the data to analysis'. Presumably this is a codification of all relationships of the basic variables of nature that entail everything about everything else given sufficient manipulation....

(3) In such a description, nothing would be uncertain (for the subject of 1 which has the specification procedure in 2). — fdrake

Which brings us back to the point I've been trying to make. In sufficiently complex systems, which are not all that complex, (1) and (2) are not humanly possible and therefore (3) is false.

a football ....(which is very spherical) — fdrake

As everyone knows, a football is not spherical, it is oblong with pointy ends.

If we flip a coin a thousand times, we can be pretty confident that 50% of the flips will be heads. If we lack confidence in logic, we can do it and then be happy that we can predict the future. — frank

Actually, if I flip a coin 1,000 times, it's unlikely that exactly 50% of the flips will be heads. It is certain, though, that if I flip 1,000 times and it isn't 50/50, if I keep flipping, it will eventually even out to 50/50. I'm not trying to nitpick here. It seems to me to be a pretty important distinction.

If we flip one coin, we know zero, nada, not-a-fucking-thing about the outcome (unless the system is rigged or we have Laplace's demon on hand.) I'm sure you agree with that? — frank

As @fdrake says, knowing that there is a 50/50 chance it will come up heads is not "nada." It's more than we know about lots of things that are a lot more important than coin flips.

'if we knew all relevant information then the future would be fixed' — fdrake

As I've said, there are times when knowing all relevant information isn't possible, even in theory. Even if it were possible, that information would also have to be processed in order to make a prediction.

Our knowledge is fallible. Randomness is the result of a lack of knowledge of some system. Once we acquire the necessary knowledge the system becomes predictable. Predictions and randomness are ideas that exist in one's head as a result of one's knowledge. What may appear random to you is predictable to me because we both have different knowledge of the system. — Harry Hindu

If I were to write a complex computer program for the behavior of a human-like robot, there would most likely be bugs that would need to be worked out after the initial release. The program is so complex, and its interactions with the world so varied, that I can't predict the outcomes of every type of interaction that may occur. This isn't because the world is indeterministic. It is because my knowledge and memories are limited. — Harry Hindu

As I said previously:

There is a point....where "completely outside the scope of human possibility" turns into "not possible even in theory." — T Clark

At that point, in my, and others, opinions, it stops being deterministic.

One thought that comes to mind, is that, unless you're a systematic philosopher, the world is not a system. It is rather more like what is required for there to be systems. But I am inclined to believe that the world must transcend any notion of 'system'. — Wayfarer

That quote was from the journal paper Wittgenstein linked me to. I wasn't trying to make a point by using that word. If it confuses things, we can just use one of the other definitions. That's why I like to provide more than one when I can.

What I think Frank is referring to is directly relevant, and as it hasn't been spelled out yet, let's do it. 'LaPlace's Daemon' says:

We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.

— Pierre Simon Laplace, A Philosophical Essay on Probabilities.

Now, regardless of the merits of this statement in light of what has happened since 1814, when it was published, I feel as though this statement is hugely relevant to this thread, as I think this is the source of the whole idea of 'determinism' which so many people who turn up on this forum and post seem to take for granted. — Wayfarer

How is that different than the definitions of "determinism" provided in the OP? Obviously, it provides a more detailed description, but otherwise I don't see any inconsistency. I don't know if you read the article, but the authors call out this specific quote for criticism.

I often feel like asking them if they've heard of [Werner Heisenberg], but I'll hold off for now. — Wayfarer

I specifically left out quantum mechanics from this discussion because I wasn't sure how it fit in. I have no objection to you bringing it up. It is my understanding that QM is considered a deterministic theory.

Sure, you can say that. But there is nothing stopping people speculating as to whether nature is deterministic or indeterministic, and finding that such speculation does make sense to them. — Janus

Yes, I agree completely. "You can say that, but there is nothing stopping people speculating.." Sounds like a definition of "philosophy" to me.

I say this all the time - This is a metaphysical/epistemological issue. It's not a matter of fact, it's a matter of choice and usefulness. I think making the distinction between determinism and predictability is not useful in most cases and I think it is often misleading. Here's a quote from William James's "Pragmatism."

Pragmatism, on the other hand, asks its usual question. "Grant an idea or belief to be true," it says, "what concrete difference will its being true make in anyone's actual life? How will the truth be realized? What experiences will be different from those which would obtain if the belief were false? What, in short, is the truth's cash-value in experiential terms?"

The moment pragmatism asks this question, it sees the answer: True ideas are those that we can assimilate, validate, corroborate and verify. False ideas are those that we cannot. That is the practical difference it makes to us to have true ideas; that, therefore, is the meaning of truth, for it is all that truth is known-as.

I guess that makes me a pragmatist.

Choatic system are deterministic but does it say in theory ( not practise ) that it is impossible to predict the future states, as you have mentioned in a discrete manner ? — Wittgenstein

That was one of the points I was trying to make. In my opinion if something is so difficult to predict that it is and will never be possible to do so, it doesn't make sense to call it deterministic. To me, that would be the same as saying even if only God can predict it, it's still deterministic. I think that's what people are saying, and I don't agree with it.

You should try to refute AUP, even though it seems wrong intuitively. Maybe it is talking about lack of information causing the unpredictability and we can perhaps predict chaotic system if the initial values are accurately known or maybe it is inherent in the system — Wittgenstein

I don't think I was clear enough. AUP doesn't seem "wrong intuitively" to me, I just don't think it changes my argument. As I said, it seems to me it's just one of the

good reasons why a deterministic system might be unpredictable. — T Clark

Or am I missing something?

And yes, I am saying that determinism and predictability are often conflated, probably at least in part due to the fact that 'determinability' and 'predictability' mean the same thing in respect of outcomes; that coupled with the obvious relationship between the ideas of determinability and determinism. — Janus

I don't think that is the reason predictability and determinism are assumed to be equivalent. I think they genuinely are, in all meaningful ways, equivalent at the point, as I said,

where "completely outside the scope of human possibility" turns into "not possible even in theory. — T Clark

At that point, it becomes what is often called a distinction without a difference. I think that's the heart of my argument. To me, if prediction of a system's behavior is "not possible even in theory," it doesn't make sense to say it is deterministic.

You flip a fair coin, the probability of heads is 0.5, the probability of tails is 0.5. The outcome is not predictable, but the probabilistic behaviour can be fully specified. Whether this behaviour arises from true randomness or as a result of an intricate dependence of the dynamics of coin flipping to the forces applied to lend it rotation and project it through the air, the distribution of heads and tails is still part of the system. Probability's a latent structure of even fully deterministic systems. — fdrake

When I look at the definitions of determinism above, it seems to me it's talking about, not the ability to predict that after 1,000 throws there will be about 500 heads, but the exact sequence of results - h,t,h,h,t,t.....t,h, h, h, t, t.

Seems to me that probability has a place in this discussion, but I'm not exactly sure how. Maybe I have not been clear enough about what I mean by 'predictable."

Just to be clear, I disagree with the quote you attributed to me. That's not my position, it's the position of the paper I referenced.

I think the reason these two notions are often conflated is, in part at least, due to the fact that determinability and predictability are, in some sense, synonymous. — Janus

It seems you're saying they are conflated because they mean the same thing.