Reductive materialism doesn't make any assumptions about what the nature of the physical is. What it argues is that mental phenomena can be reduced to physical phenomena – which seems to be exactly what is meant by "we are exhaustively physical beings". — Michael

Even if we are exhaustively physical beings it doesn't follow that our wills are brain states, but merely that they are physical in some sense we may have no understanding of.

If free will requires a rejection of causation then it requires that one's actions are uncaused, i.e. spontaneous. Does it really make sense to say that we have free will if our actions occur spontaneously? — Michael

It only requires that acts of free will are not caused by anything beyond that will. If our will is spontaneous how would that contradict it being free?

Even if we are exhaustively physical beings it doesn't follow that our wills are brain states, but merely that they are physical in some sense we may have no understanding of. — John

So your notion of free will depends on a notion of the self that we have no understanding of? In which case we have no understanding of what it means to have free will.

If our will is spontaneous how would that contradict it being free?

That depends on what it means for one's will to be free. Some might not consider a spontaneously-occurring will to be free.

And what's the relevant difference between a spontaneously-occurring will and a causally determined will?

I don't think we have any more understanding of the self than we do of freedom. What we do have is an intuitive feeling of both; that we can either choose to accept or reject. It remains a leap of faith either way. The important philosophical question is not whether the self or free will 'really exist', but whether we should believe in our own intuitions about them, and accept their unanalyzability, or whether we should follow the current intellectual fashion and reject them because they cannot be analytically modeled. I think that, like all important ethical questions it is a matter for the individual.

It's true that some might not consider a will that functions spontaneously to be free, but I can't see any good reason for that, because that is precisely what 'choosing freely' means. And it doesn't, as some mistakenly think, mean having no reason for choices (i.e. that choices are utterly random), rather it means not being causally determined by anything at all to make those choices, that is, to choose one reason over another freely.

I think free will, our ability to act as author without being determined to act in a certain manner is real, and it does not require a leap of faith. The physical causal argument that I am determined to do x because of some other event y does not work in the narrative I tell myself about the world.

The meanings I give to what I experience are not the same as those experiences. Meanings are mental, normatively and linguistically generated. They may depend on a deterministic universe, I don't know for sure about that, but I am sure that there are no meaning 'out there' that I have not generated, or accepted as part of a society.

What I do depends on my understanding, which is based on the meanings I have mentally, normatively or linguistically constructed for myself. The causality of the meanings I have attached to experience is not the same as these events. My reconstitution of past events are not those events. In so far as I can create meanings for myself, I have 'free will'

I'd say more that unless someone has very unusual mental phenomena, a rejection of free will is far more likely to be based on faith, since there's no good evidence that all phenomena in the world are strongly causally deterministic.

Re the other question, of course one can be an agnostic on the issue of free will. That one isn't an agnostic on the issue doesn't imply that one's view is a faith-based view, however.

Some aspect of transcendental philosophy makes enough sense to me to think we are both immanent within our factical life, and transcend ourselves within our projected possibilities to be something we are not. I think in this transcendence we are free. Not sure if faith really plays into this.

I'd say more that unless someone has very unusual mental phenomena, a rejection of free will is far more likely to be based on faith, since there's no good evidence that all phenomena in the world are strongly causally deterministic. — Terrapin Station

No idea what could constitute "good evidence", but one assumes that Reality obeys the laws of physics, which are deterministic.

No idea what could constitute "good evidence", but one assumes that Reality obeys the laws of physics, which are deterministic. — tom

By "deterministic" are you just referring to causal determinism (every event has a cause) or to the stronger nomological determinism (every event has a cause and each cause has just one possible effect)?

It's worse than that. Reality is a static space-time block.

So eternalism?

one assumes that Reality obeys the laws of physics, which are deterministic. — tom

Strong causal determinism hasn't been the received view in the sciences for something like 140 years now.

l It's worse than that. Reality is a static space-time block. — tom

And that nonsense certainly isn't the received view in the sciences.

Strong causal determinism hasn't been the received view in the sciences for something like 140 years now. — Terrapin Station

General relativity is isomorphic with the statement that Reality is a stationary block spacetime. The Wheeler-DeWitt synthesis of gravity and quantum mechanics is a stationary wavefunction. In the absence of the free will axiom quantum mechanics is superdeterministic.

So, according to the prevailing conception of science, Reality is fully determined. Given the state of reality at any time - initial, final or any time in between - and the laws of physics, it is possible to predict what has occurred, and retrodict what will occur.

We are not only at the state of knowledge where we are able to predict the big-bang, but also the fine details of that event!

Thus most educated people are avowed determinists.

General relativity is isomorphic with the statement that Reality is a stationary block spacetime. The Wheeler-DeWitt synthesis of gravity and quantum mechanics is a stationary wavefunction. In the absence of the free will axiom quantum mechanics is superdeterministic.

So, according to the prevailing conception of science, Reality is fully determined. — tom

Wait. Stop right there. There are a number of issues to bring up here, but given the way these sorts of discussions usually go, I'm just going to do one at a time.

So here's the first one:

You're claiming that the "prevailing conception of science" is the block universe theory of time simply because the block universe theory of time is isomorphic with general relativity? (Also, could you clarify if you're using isomorphic in a stricter mathematical sense or a looser sense?)

You're claiming that the "prevailing conception of science" is the block universe theory of time simply because the block universe theory of time is isomorphic with general relativity? — Terrapin Station

Not quite what I wrote, but anyway. I'd be surprised if anyone found anything non-standard, let alone contentious, in anything I wrote. Relativity mandates we take a 4D view of reality, and there is no way of escaping the block. We are space-time worms. We don't have free will.

But of course, you could argue in the other direction and show that because we *do* have free will, general relativity must be at best, an approximation. You are unlikely to convince anyone however, I've certainly not been able to.

Relativity mandates we take a 4D view of reality, and there is no way of escaping the block. — tom

So you'd say that the block universe theory of time is indeed the received view in the sciences?

So you'd say that the block universe theory of time is indeed the received view in the sciences? — Terrapin Station

Knock yourself out: https://www.quantamagazine.org/20160719-time-and-cosmology/

Matter of Faith — anonymous66

Depends on what you mean by the above. Rejection of free will requires "faith" in the scientific method which leads us to determinism.

Knock yourself out: https://www.quantamagazine.org/20160719-time-and-cosmology/ — tom

Which statement(s) in that article to you take to imply that the block theory is the received view?

Which statement(s) in that article to you take to imply that the block theory is the received view? — Terrapin Station

All of it. This is getting tedious by the way.

All of it. — tom

That would make no sense. For example, the first sentence is this, "Einstein once described his friend Michele Besso as 'the best sounding board in Europe' for scientific ideas." That in no way amounts to a claim that block theory is the received view.

This is getting tedious by the way.

It's supposed to be a conversation. ;-) I guess one could find those tedious, though.

That would make no sense. For example, the first sentence is this, "Einstein once described his friend Michele Besso as 'the best sounding board in Europe' for scientific ideas." That in no way amounts to a claim that block theory is the received view. — Terrapin Station

Do I have to cut and paste the entire article, paragraph by paragraph?

Einstein once described his friend Michele Besso as “the best sounding board in Europe” for scientific ideas. They attended university together in Zurich; later they were colleagues at the patent office in Bern. When Besso died in the spring of 1955, Einstein — knowing that his own time was also running out — wrote a now-famous letter to Besso’s family. “Now he has departed this strange world a little ahead of me,” Einstein wrote of his friend’s passing. “That signifies nothing. For us believing physicists, the distinction between past, present and future is only a stubbornly persistent illusion.”

That last statement is tautologous about physicists who believe that, though. That's different than it being a received view.

For us believing physicists, the distinction between past, present and future is only a stubbornly persistent illusion.” — tom

Why is that illusion so stubbornly persistent?

I've always loved the notion of the 4D universe. Is this not perfect closure? It's like Parmenides, sort of. I've heard metaphysics described as exactly the flight from time and chance. So the Block is like the central erotic object of the meta-physician.
But even if I "knew" it was true, I would live with the burden of decision.I would constantly make choices that I could not unmake, not knowing what waits further off in the woods in that direction or what I sacrificed in the other direction not taken. So the truth of the Block would only be an abstract comfort, assuming the continuation of worldly hopes and fears. In short, man is condemned to at least feel like he's free, most of the time, anyway. Do we want call our usual state "false", even if in some sense it is ? It's all about this "in some sense," I suppose.

Not quite what I wrote, but anyway. I'd be surprised if anyone found anything non-standard, let alone contentious, in anything I wrote. Relativity mandates we take a 4D view of reality, and there is no way of escaping the block. We are space-time worms. We don't have free will. — tom

This seems wrong. The general theory of relativity is not inconsistent with the laws of physics being indeterministic. GR is a deterministic theory of gravitation, but gravitation doesn't govern everything that happens in nature. GR is distinguished from Newtonian gravitation by the specific way in which it specifies the metric of spacetime as a function of the stress-energy tensor (a mathematical entity that specifies the energy and momentum flux and density at each point of spacetime); whereas Newton's theory makes the gravitational field dependent merely on the instantaneous distribution of (invariant) mass. Either theories are deterministic and both are consistent with a 4D block universe depiction. If, however, the laws of physics that govern the evolution of the stress-energy tensor itself (which merely is an input for the determination of the gravitational field in GR) are non deterministic -- as they likely would be from our empirical perspectives if quantum mechanics were right, under some interpretations -- then the 4D depiction of the universe would be invalidated. In that case one would rather have a branching out picture of the universe, with any specific contingent history of the whole universe (i.e. one single "branch") satisfying independently Einstein's field equations. There is thus no inconsistency between GR and physical inteterminism.

In any case on my view physical determinism doesn't entail universal determinism, and the possibility of (mere) physical determinism has little bearing on the philosophical problem of determinism, free will and responsibility.

Newton's gravity is incompatible with special relativity: it allows action at a distance and is not Lorentz invariant. Whatever you might want to construct out of "gravity", it can't be a 4D spacetime block with a Lorentzian signature, and no such construction is forced upon you. Under relativity it is unavoidable. So Newton's laws are deterministic, i.e. the future is determined by the past, while according to relativity, the future already exists. Under gravity, time is a universal parameter, under relativity, it is a dimension. If you were to describe relativity as fatalistic I wouldn't argue.

As I mentioned earlier in the tread (perhaps more than once), free will is axiomatic in science and explicitly so in quantum mechanics. If you remove the free will axiom - or the FW loophole as some prefer to call it - then, quantum mechanics is superdeterministic.

Newton's gravity is incompatible with special relativity: it allows action at a distance and is not Lorentz invariant. — tom

Of course not. It is rather invariant under Galilean transformations.

Whatever you might want to construct out of "gravity", it can't be a 4D spacetime block with a Lorentzian signature, and no such construction is forced upon you. Under relativity it is unavoidable.

The Lorentzian signature is a feature of the metric of spacetime, and, it is true, encourages the '4D block' picture since it does away with the idea of a unique present moment univocally defined throughout all of space (i.e. it does away with a uniquely defined space-like hypersurface). Hence, if there is no such thing as the present state of the universe, one may be tempted by the alternative idea that the universe exists, in a sense, all at once. But that still is optional. There can still be a local definition of the present, and there still remains regions of spacetime that belong to the absolute pasts and to the absolute future, from the point of view of an observer (namely: the past and future regions of the light-cone centered where (and when) the observer is located) and, if the overall laws of physics (besides Einstein's field equations) are indeterministic, then GR is a true theory and the universe still branches out. The 4D picture is still out and not forced upon you either by special or general relativity.

In short, physical determinism is an open question regardless of the truth of GR; and the falsity of physical determinism is inconsistent with the "4D block" picture.

Try this http://philsci-archive.pitt.edu/2408/1/Petkov-BlockUniverse.pdf

You are simply refusing to accept an inescapable consequence of our best theories. Nothing in reality has ever been discovered to contradict GR, or the standard model, both of which are time-symmetric theories.

This is why most scientists don't believe in free will, because it doesn't fit with what they know.

Try this http://philsci-archive.pitt.edu/2408/1/Petkov-BlockUniverse.pdf — tom

Thanks for the reference. I'll read it carefully. At first glace, though, it seems like the author advocates his block universe view as the only possible alternative to presentism (the view that only the present exists). Although I don't endorse the block universe view, I am not endorsing presentism either. In The Fabric of Reality, David Deutsch has effectively argued against presentism, it seems to me, without thereby endorsing anything like the block universe view. I don't think either view is coherent, and both seem reliant on what Hilary Putnam has criticized as metaphysical realism. (This is a criticism that Putnam developed after he had published the paper Time and Physical Geometry Petkov discusses). So, Petkov may be arguing on the basis of a false dichotomy.

You are simply refusing to accept an inescapable consequence of our best theories. Nothing in reality has ever been discovered to contradict GR, or the standard model, both of which are time-symmetric theories.

I have not suggested that anything that we know contradicts GR (although we don't yet have a quantum theory of gravitation, and so GR is at best an incomplete theory, nothing that I said depends on GR being inaccurate at any level). Rather I am questioning the validity of your inference from the truth of GR (or from the truth of special relativity) to the idea that the block universe is a mandatory view.

This is why most scientists don't believe in free will, because it doesn't fit with what they know.

While some scientists are hard determinists, other philosophically informed scientists rather are compatibilists about the issue of freedom and determinism, so you are seemingly making another unwarranted inference. Even if the block universe view were correct, this would not entail that we must reject the reality of free will, unless one would also provide a convincing argument against compatibilism. Such arguments usually are of a philosophical nature -- relying on the conceptual analysis of the very ideas of agency, freedom and responsibility -- rather than being based on empirical physical theories that have little relevance to the elucidation of those concepts.