Determinism is the belief that every action in time is born by the previous one. [1] In deterministic terms you cannot have an event E if you didn't have an event D before, which in turn is the result of a cause C and so on, without any type of alphabetical bound. This philosophical conception is one of the most discussed, directly or indirectly, because it is the generator of very important ontological implications, first of all the existence of free will which, we could claim, is one of the most courted topics by the philosophers of all time. Something that has always struck me about the endless debates on the subject it is a simple logical flaw that people seem to commit when they put forward their arguments, both for and against determinism. This (ir)rational weakness lies in the very concept core of determinism itself and, for simplicity, I will call it the "What if ?" problem. It goes like this:

  • " If determinism is true, then should criminals be persecuted for their crimes ? "
  • " If determinism is true, then should science cease to exists ? "
  • " Why, if determinism is true, do we look carefully before crossing the road ? "
  • " If determinism is true why should I do anything ? "

I think you got the point. Now, questions like these can be found in countless publications, online blog discussions, talk with friends on a drug-induced Friday night and they generally give way to endless verbosity flows, some of which may also contain angular viewpoints that shed new lights on your beliefs. So far so beautiful, too bad all these intellectual disputes are inconsistent with the very premise of determinism. Think of the first question, the only correct answer is:

  • "If determinism is true, criminals will continue to commit crimes and we will condemn them for this, we could not change our way of acting because otherwise it would not be determinism."

The second answer is a reflection of this and also the third. In fact, this answer is a blueprint for every possible observation to such questions which, notice well, make up a good 95% of the total discussions on the material. The same errors are dragged by induction into the reasoning on any type or by-product of the main theme.
For example, I remember a post on reddit in which a user wondered if, taken as assumption the veracity of eternalism (block universe determinism [2]), then it would have been more ethically appropriate for human beings to stop having children because you know, life is unfair and in this way those poor beings would suffer forever. To this my answer was the following:

  • "If eternalism is true nothig is created. Everything already exist. You fail to see it from a 4D perspective. Everything is already arranged, begginning to end, every state of matter, every permutation of it all. There is no movement, no action, no intention. "

You can observe a certain isomorphism between this answer and the one given above. If you want to explore these concepts (eternalism and its philosophical, physical and ethical implications) in a baroque, literary fascination, I strongly recommend the monumental novel Jerusalem by Alan Moore [3]. Nowadays science has not yet succeeded in proving the existence of a single random natural source and even if quantum physics seems to put sticks in the wheels of determinism, my personal belief is in line with that of nobel prize Gerard 't Hooft [4] , which hypothesizes that there may be a mechanistic structure at the base of everything, of which quantum physics is nothing more than an emergent property that we do not yet fully understand [5][6]. However, the thesis of this post is not to affirm the existence of determinism, the thesis, to make it short, is to affirm that determinism (in all its spectrum of forms) is a sort of ontological cul-de-sac. I don't think we will ever be able to design experiments, physical or psychological, that can prove or disprove it, let alone arrive at a solution through the tools of logical investigation. The existence of determinism could very well be an undecidable problem. Psychological studies have already been conducted, showing that people who believe in determinism are less productive, flirt more easily with depression and have a more creaky morality than others but these studies (and consequently the results) fall into the same categorical errors analyzed above. If everything is carved in the marble of time, we cannot change things in any way and people who believe in stochastic salvation do it because they cannot do otherwise and are (generally) more serene because they cannot do otherwise. In essence, in my opinion, it is impossible to determine whether a system is deterministic or not from within the system itself. Determinism, as a concept, can develop the same sometimes annoying and sometimes fascinating self-referentiality of the halting problem.





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"There's no free will," says the philosopher;

"To hang is most unjust."

"There is no free will," assents the officer;  

"We hang because we must."

-- Ambrose Bierce



In the same vein—previously, on “Rationality Quotes”:

“It’s my fate to steal,” pleaded the man who had been caught red-handed by Diogenes.

“Then it is also your fate to be beaten,” said Diogenes, hitting him across the head with his staff.

If determinism is true, what's the point of X

To anybody seriously asking a question in this category, check your assumptions. The "point" is a symbol on the map that corresponds to a relationship between X and a particular mind. (Or, more precisely, it corresponds to an aspect of how the mind analyzes that relationship.) Indeed, if it has any causal bearing on X at all, I expect the "point" will turn out to be little more than part of a reflection in the mind of the proximate causes and conditions leading to X. Else, the "point" is probably caused in the mind by X. In any case, the universe doesn't need a "point" for anything: it just keeps unfolding regardless of how the minds it contains may or may not assign map symbols regarding (read: feel about) any particular event in the unfolding.

In context, a point means a purpose, and a purpose tends to mean making a difference...which is where the trouble starts, because there are no differences to be made under determinism.

A difference requires a reference point from which to differ. Even in a deterministic system, minds thinking about the future probabilistically can calculate counterfactuals that would suffice to fulfill this need.

Yes, but that's not the issue. It's not that determinism prevents you calculating the results of actions, it's that actions can't make a difference... the future is inevitable, and your decision making processes, however careful or slipshod are as well.

My mind keeps wanting to interpret your take on determinism as a fatalistic fallacy. Let me try to get some clarity on this.

If belief in determinism causes someone to make poorer choices, they're doing it wrong. Do you agree? If not, why?

If belief in determinism causes someone to make poorer choices

If determinism is actually true, this condition is false. Belief in determinism is correlated with worse outcomes, but one doesn't cause the other; both are determined by the state and process of the universe. Minds thinking about counterfactuals is just part of the (determined) universe, and their conclusions are also determined. Free will is an illusion that some kinds of brains create after the fact to explain what happened to themselves.

Note that I don't actually know this is true, nor how I'd prove or disprove it. My intuition (which may be just a side-effect of the universe) is that there is something about me that makes decisions which influence future experiences. Since I can't think of any evidence that would shift my beliefs, I'm going to call it a modeling choice rather than a truth. I prefer (or am destined to prefer) a semi-free choice model, where there is a thing that has beliefs which correlate with the branch of the universe it finds itself experiencing. It doesn't matter whether counterfactual me experience something else, or if they don't exist, or if the causality is illusory. The correlation is so strong and clear that I'm forced to (heh) act like it's causal.

Belief in determinism is correlated with worse outcomes, but one doesn't cause the other; both are determined by the state and process of the universe.

Wait, how does determinism obviate cause and effect? A timeless universe would, but deterministic causation is still causation, right? Not that it matters for the point at hand.

(I'd prefer a better term than "correlated", there's still some logical determination going on there. Not sure what to replace it with, though.)

The point is, it doesn't matter if we live in a deterministic universe. Our values are still best served by pursuing them with our full effort, even if from some omniscient outside perspective the whole thing were predetermined. If modeling ourselves as deterministic would diminish our efforts, we'd be making a mental mistake.

If we do live in a deterministic universe, then free choice is simply what the unfolding of the determination feels from the inside. As far as I can tell, the ontological details don't make much empirical difference and our intuitions are well-optimized for performance. I think I've somehow managed to update for the possibility of a timeless universe on the intuitive level but the difference is so small it's hard to tell. Feel free to stick with what you have, I guess.

Belief in determinism is correlated with worse outcomes, but one doesn't cause the other; both are determined by the state and process of the universe.

Read literally, you seem to be suggesting that a deterministic universe doesn't have cause and effect, only correlation. But this reading seems prima facie absurd, unless you're using a very non-standard notion of "cause and effect". Are you arguing, for example, that it's impossible to draw a directed acyclic graph in order to model events in a deterministic universe? If not, what are you arguing?

I mean to say that the idea of cause and effect is ... different, in a purely deterministic universe. Every state of the universe exists in a 4D (or more) volume, the idea that time is different from other dimensions is illusory. There is one state at a time and another state at another time. This may be what you mean by "timeless universe" - if every state is determined, then time is no different from distance.

Much like we can call configurations of atoms that don't have a lot of empty space between them "joined", we can call clusters earlier in time "causal" for those later in time. But this is map, not territory. There is likely some underlying complexity-reduction that does mean the whole shebang (universe from big bang to heat death) comprises fewer bits than a naive encoding, and this can be modeled as causality - patterns of time-adjacent configurations. You can draw the graph that models the events in a particular way, but that's just a modeling choice rather than a reality.

(and to reiterate, this isn't my preferred conceptualization of the universe, but I can't think how to disprove it. Same for simulation or Boltzmann brains or other acknowledgement that my perception and memory is darned limited - I don't prefer them as guiding models, but I can't disprove them. I'll even agree that determinism is prima facie absurd, much like the earth being round or the implications of special relativity are absurd. )

But this is map, not territory.

Certainly. Decision-making itself is also a process that occurs in the map, not the territory; there is no contradiction here. Some people may find the idea of decision-making being anything but a fundamental, ontologically primitive process somehow unsatisfying, or even disturbing, but I submit that this is a problem with their intuitions, not with the underlying viewpoint.

(If someone goes so far as to alter their decisions based on their belief in determinism--say, by lounging on the couch watching TV all day rather than being productive, because their doing so was "predetermined"--I would say that they are failing to utilize their brain's decision-making apparatus. (Or rather, that they are not using it very well.) This has nothing to do with free will, determinism, or anything of the like; it is simply a (causal) consequence of the fact that they have misinterpreted what it means to be an agent in a deterministic universe.)

If someone goes so far as to alter their decisions based on their belief in determinism

You're mixing levels. If someone can alter their decisions, that implies there are multiple possible next states of the universe, and that strict determinism is wrong. If the universe is actually determined, nobody alters any decisions, they just experience the decisions they are calculated to make.

You're mixing levels. If someone can alter their decisions, that implies there are multiple possible next states of the universe

This is incorrect. It's possible to imagine a counterfactual state in which the person in question differs from their actual self in an unspecified manner, which thereby causes them to make a different decision; this counterfactual state differs from reality, but it is by no means incoherent. Furthermore, the comparison of various counterfactual futures of this type is how decision-making works; it is an abstraction used for the purpose of computation, not something ontologically fundamental to the way the universe works--and the fact that some people insist it be the latter is the source of much confusion. This is what I meant when I wrote:

Decision-making itself is also a process that occurs in the map, not the territory; there is no contradiction here.

So there is no "mixing levels" going on here, as you can see; rather, I am specifically making sure to keep the levels apart, by not tying the mental process of imagining and assessing various potential outcomes to the physical question of whether there are actually multiple physical outcomes. In fact, the one who is mixing levels is you, since you seem to be assuming for some reason that the mental process in question somehow imposes itself onto the laws of physics.

(Here is a thought experiment: I think you will agree that a chess program, if given a chess position and run for a prespecified number of steps, will output a particular move for that position. Do you believe that this fact prevents the chess program from considering other possible moves it might make in the position? If so, how do you explain the fact that the chess program explicitly contains a game tree with multiple branches, the vast majority of which will not in fact occur?)

There are various posts in the sequences that directly address this confusion; I suggest either reading them or re-reading them, depending on whether you have already.

I mean to say that the idea of cause and effect is … different, in a purely deterministic universe. Every state of the universe exists in a 4D (or more) volume

You are taking determinism to mean eternalism, and it doesn't.

I am not arguing that you should or should not believe in determinism because of the affect it has on the quality of your decision making. The issue is whether you can make decisions at all, in a certain sense, that is making decisions that make a difference. If determinism is true, your decisions will be as good or bad as they are determined to be, but even if you are making very good decisions in a decision theoretic sense, they are not doing certain things, such as steering the course of history, making a difference, etc. They lack a "point" in that sense.

Counterfactually, if your decisions were different, the future-ward implications of those decisions would be different. In that sense, they do have a point.

I wasn't trying to ask whether one should believe in determinism or not. I was asking what effects belief in determinism should have.

Counterfactually, if your decisions were different, the future-ward implications of those decisions would be different. In that sense, they do have a point.

What kind of things a counterfactual could be depends on the truth of (in)determinism. If determinism is true,then the path untaken was never physically possible, and counterfactuals are purely conceptual. What kind of difference-making does that support? If you didn't exist (which is impossible) then the future would be different, likewise if you were different or made a different choice -- in each of the three cases it's not possible for the counterfactual situation to occur.

Under determinism, you can choose between physically possible outcome A and physically possible outcome B, and the counterfacutal, the untaken choice, could have been take, so your choice brings about a future that was not inevitable. That's a much stronger sense of "making a difference".

I wasn’t trying to ask whether one should believe in determinism or not. I was asking what effects belief in determinism should have.

If belief in determinism causes someone to make poorer choices, they’re doing it wrong. Do you agree? If not, why?

Belief in determinism shouldn't cause someone to make poorer choices from a decision theoretic, utility-maximisation perspective, but that ins't the whole issue. There's also a bunch of issues starting with the fact that (in)determinism does affect what a choice is. It affects the existence of moral agency, and the justifiability of moral praise and blame. People aren't isolated agents making decisions that affect only themselves, so treating "winning" as the only issue that matters is a evaluative mistake.

There's long been an argument about whether (non) existence of genuine volition and moral agency should affect our thought and practice about ethics and jurisprudence.

As far as I can tell, these dissonances usually result from an ontological-type mismatch, eg. a free-willed agent judging the choices of a deterministic one. Within-universe, moral choices and moral judgments are of the same ontological type and the dissonance cancels out.

These kinds of moral judgments only make sense between roughly equal agents anyway. If one is so much more capable that it can model the other as basically deterministic, it is better off exerting influence through causal channels.

Nothing about the type of a universe determines the content of a judgement. Anyone can have a false belief in any universe. Determinists typically believe that many people have false beliefs about freedom and responsibility.

You have misunderstood the kind of issue I am talking about. I am not talking in terms of solipsistic decision-making, or ethically unloaded attempts by one agent to predict another, I am talking about why societies pin medals on one person and put another in the stocks.

This sort of thing: https://plato.stanford.edu/entries/moral-responsibility/

I know. My claim is that the issue stems from the way our moral intuitions are grounded in the intuitive notion of free will. If we update to a deterministic world-model without updating the intuitions, we get the confusions you describe.

To clarify, deterministic agents rewarding and punishing deterministic agents only seems more problematic than the nondeterministic case because of our nondeterminist intuitions.

  1. We have no pressing need to update, since we don't know that determinism is true or that compatibilism is false.

  2. Please state your assumptions. Other people might not agree with them.

1. True. However, as long as we are discussing determinism, it is proper to avoid the intuitive confusion.

2. Help me out here. Which unstated assumptions do you think I have?

I'm engaging in this conversation because you seem to be almost-but-not-quite arguing against determinism in a way that suggests you may be operating from nondeterminist intuitions. I've been trying to figure out if that was the case and discussing the philosophy as it comes up.

What are your own assumptions on this? How do your intuitions mesh with the possibility of living in a deterministic universe?

  1. In which direction? Remember, if compatibilism is true there is no need to give on standard intuitions.

  2. Determinism=true, compatibilism-false.

1. The problem with that is, the standard intuitions implicitly assume that determinism is false. It's hard to have a productive discussion about a counterintuitive topic if the contrary intuitions keep firing.

2. I believe that determinism is plausible but I don't have strong ontological commitments at this time. Based on the trajectory of the conversation, I suspect you have a strong (implicit or explicit) commitment to nondeterminism. Do you?

It's also hard to have a good discussion under the tacit assumption that determinism is true, and the answer is to avoid tacit assumptions.

Tu quoque, my friend. From my perspective, your reasoning is tacitly relying on intuitive assumptions that don't apply in the (hypothetical) domain of a deterministic universe. In other words, you're implicitly assuming your conclusion.

If determinism is true, you're already a deterministic being in a deterministic universe. I suppose there's a mental trick of flipping the perspective from the outside to the inside, but that may require taking the hypothesis more seriously than you're likely to do.

Remember, people like me started out with the intuition of nondeterminism. We've already worked through the basic objections about things like choices, consequences and morality. If your wish is to engage productively on this topic, you may want to rethink your approach.

Tu quoque, my friend. From my perspective, your reasoning is tacitly relying on intuitive assumptions that don’t apply in the (hypothetical) domain of a deterministic universe. In other words, you’re implicitly assuming your conclusion.

What do you think I am reasoning toward?

Remember, people like me started out with the intuition of nondeterminism. We’ve already worked through the basic objections about things like choices, consequences and morality.

But you don't have a proof of determinism. People like you keep advising me that I need to "update" and treat determinism as true, and drop all intuitions counter to it, ahead of the evidence.

You keep commenting on determinism but given your intuitions, you end up sounding a bit like "Nondeterminism, therefore X." In reply, people tell you something like "If determinism, then Y."

This is the important point. If determinism is true, then nondeterminist intuitions are mistaken. What's the point of participating in discussions of determinism if you keep applying intuitions that take its falsity as an axiom?

If determinism is true, then nondeterminist intuitions are mistaken.

If determinism is true and compatibilism is false.

You keep commenting on determinism but given your intuitions, you end up sounding a bit like “Nondeterminism, therefore X.”

I have pointed out what people worry they are going to lose under determinism. Yes, they only going to have those things under nondeterminism..that's just another way of saying the same thing.

I have pointed out what people worry they are going to lose under determinism. Yes, they only going to have those things under nondeterminism.

You just said that nondeterminist intuitions are only mistaken if determinism is true and compatibilism is false. So what exactly is being lost if you subscribe to both determinism and compatibilism?

That's the bone of contention. Compatiblists say nothing that's "worth having", their opponents say otherwise. It's hard to dispute that the ability to choose between really possible alternatives goes missing.

If determinism is true and compatibilism is false.

Huh. Going by the wikipedia definition of compatibilism, it seems like a distinction without a difference. How does it help in your view?

I have pointed out what people worry they are going to lose under determinism.

This feels like worrying about losing the colors of the rainbow if optics is true. Maybe add that worry to the list of potentially mistaken intuitions.

Previously, you said that people need to give up their intuitions about free will. Well, under full strength compatibilism, they don't. That's the difference.

This feels like worrying about losing the colors of the rainbow if optics is true.

Care to turn that feeling into an argument?

Not giving up, updating. The whole point is that determinism (or timelessness for that matter) need not invalidate our notions of agency, consequence or morality. If it feels like it does, that's a bug in the system.

The whole point is that determinism (or timelessness for that matter) need not invalidate our notions of agency, consequence or morality.

Care to turn that assertion into an argument?

Okay, let me try to put it this way.

Imagine someone giving you orders while holding a gun to your head. That situation feels distinctly unfree, even though you're entirely free to disobey and take the bullet to the head.

Our intuitive sense of freedom may actually refer to a lack of externally imposed constraints on our decision process, as opposed to some inherent internal quality. The mistake would then be imagining determinism as an external imposition when it would in fact be a quality of the decision process itself.

Does that help?

Thats a standard argument for compatibilism. It isn't considered a proof of compatibilism, because that would require assuaging all the worries that people have, and not just the subset compatibilist have ready answers for. I've already put forward another issue which is harder to answer from the compatibilist perspective: making a difference.

Are you sure that isn't the same type of confusion? The way your decision process goes does make a difference to the outcomes of the universe. Again, being predictable-in-principle is a property of the process, not an external imposition.

If my decision making process could not be different , how does it make a difference? I have already covered the difference between logical counterfactuals and real countefactuals.

You consider a number of choices. You judge them according to your decision criteria and choose the one that seems best. What difference does it make if some hypothetical omniscient observer could tell in advance which choice you'll make? You'll still choose just one, and you want it to be the best one.

In what sense is the unchosen counterfactual a real one?

You consider a number of choices. You judge them according to your decision criteria and choose the one that seems best. What difference does it make if some hypothetical omniscient observer could tell in advance which choice you’ll make? You’ll still choose just one, and you want it to be the best one.

You are portraying decision making as always having a determinate outcome, and that isn't even true if computational decision making.

In what sense is the unchosen counterfactual a real one.

As examined before the... in the sense that if my decision making was indeterminate, then I could have decided differently, meaning that counterfactual was real in the sense that it could have occurred.

Unless you want to postulate some sort of branching-future superposition, there will be one eventual outcome. How do we disambiguate between objective indeterminacy in a nondeterministic world and subjective indeterminacy in a deterministic one?

It now occurs to me to wonder how antideterminists feel about books and movies. Does it diminish their enjoyment to know that the plot has already been determined?

Unless you want to postulate some sort of branching-future superposition, there will be one eventual outcome.

That's not the point. Under determinism, the one outcome had to happen, had prior probability 1.0. etc. Under indeterminism, it didn't have to happen and the alternatives had non-zero probability. You can't infer from the fact that something happened to the conclusion that it happened inevitably and necessarily.

I agree and didn't intend that to be the main thrust of my reply. Let me repeat:

How do we disambiguate between objective indeterminacy in a nondeterministic world and subjective indeterminacy in a deterministic one?

I'm asking because I expect the two to be subjectively indistinguishable and your answer should help shed light on the nature of our disagreement.

I'd also like to hear your take on the books-and-movies question.

How do we disambiguate between objective indeterminacy in a nondeterministic world and subjective indeterminacy in a deterministic one?

I’m asking because I expect the two to be subjectively indistinguishable and your answer should help shed light on the nature of our disagreement.

I don't expect them to be be objectively indistinguishable for reasons I've already stated, to do with Bell's theorem and so on. (And even if they are not distinguishable, they have very different implications).

The books and movies question seems like a disguised argument. People don't like reading the same thing over and over, and don't like spoilers, so there is a case that the subjective surprise if the ending is what matters even if it is determined. But that doesn't generalise to subjective indeterminism being the only kind that matters. Because people don't just passively consume books and movies, people also try to change objective states of affairs.

Because people don't just passively consume books and movies, people also try to change objective states of affairs.

Deterministic or not, we are the process by which change happens. I now wonder what kind of agency would satisfy your objection. Must our choices be uncaused causes? If not, what kind of causal influence is permitted?

Naturalistic libertarians usually appeal to mixtures of determinism and indeterminism, occurring in different parts of the brain or at different stages in the decision making process.

[+][comment deleted]5y10

I want to focus on the claimed logical fallacy.

"Assume X. X-> Y is inappropriate. We do Y. Why we are doing Y as it is pointless?" is kind of sloppy or incomplete logical thinking. One is mixing assumtions and observations. However the repair options seem pretty obvious that automatic steelmanning seems temping to assume.

"Assume X. X-> Y is inappropriate. We do Y. We do not seem to believe X" is perfectly fine argument ad absurdum.

"X- > Y is inappropriate. We do Y. Thefore not X." is also fine argument ad absurdum.

On the actual determinism side:

If I have a perfectly clockwork piece of code I can talk about the code doing stuff even if there is no possibility that it would run differently. It's illustrative to think how things would turn out if a piece of code was missing/different but it is not needed fundamentally to give the concepts meaning. On human level affairs "freedom" means something along the lines of "the system has degrees of freedom that include multiple meaningful outcomes" and we don't differentiate strongly between epistemic degrees of freedom and ontological degrees of freedom. Determinism works on a differnt concept layer and while it's not totally irrelevant it doesn't enter as directly relevant as a sloppy thinker would say.

It is possible that a system could be non-deterministic in the determinism way and fail to be determnistic in the human living way. A system that has degrees of freedom all of which correlate to one meaningful outcome would be humanlevel clockwork and physics level non-clockwork. And a physics level clockwork can still be unknown so that socially we must account for all meaningful categories it could turn out to be. For example if a code has a bug the programmer in the course of debugging will narrow down the search on which exact version of the code actually exist as the previous coding actions are consistent for multiple of them. Unchecked portions of it then exhibit "freedom" althought on mechanical level the code runs in only one way.

Crossing from "reasonable doubt" to "beyond reasonable doubt" has little to do with ontology and is analogous to the code bug hunt. Being deterministic is not an effective defence to claim that you do not contain bugs.

The existence of determinism could very well be an undecidable problem.

In essence, in my opinion, it is impossible to determine whether a system is deterministic or not from within the system itself.

With a good night's sleep and a clear(er) morning head, I feel better able to think about this problem. Surface thoughts:

  • I think I agree at the moment that you probably cannot prove that you live in a non-deterministic system. There is always the lingering doubt that any randomness you find is, as credited to Hooft, an emergent effect of some underlying system you simply don't (can't?) understand yet.
  • If the system is deterministic, you may be able to unravel all of its mysteries. If your system of Physics is sufficient to describe predict everything that you can observe, then there is no reason left to doubt the system's determinism. Make no mistake, though: that is an extremely high bar.

I apologize in advance if my reasoning seems incorrect. I was very surprised by your "the only correct answer is". Let's look at a simple chain:
criminals will continue to commit crimes => we will condemn them for it.
You affirm that with the truth of determinism this cannot be changed. (we could not change our way of acting because otherwise it would not be determinism). What is the reason?
Assume
A (crime) => B (condemn), but it does not follow from this:
A & A '& A' '.... => B
 Is it during determinism that we, by changing the initial data, cannot change the result? (we could not change our course of action, because otherwise it would not be determinism).
(It is possible that there are problems with misunderstanding due to the translation, correct me if this is the case)

A couple of points.

I don't know why you are so despairing of resolving the question. Bell's inequalities are a testable theory about determinism, and others might be possible.

You keep switching between determinism and eternalism, but they are not the same thing. The former is a subset of the latter, roughly

A couple of points to your points.

1) Bell's inequalities only seem to disprove local realism. In addition, many scientists criticize the assumptions and, in any case, they are compatible with different deterministic systems or with non-local hidden variables, so it is far from being a definitive tool to prove or disprove determinism.

2) If you take determinism in the broad sense as the main subject of the discourse, then eternalism is a subset of determinism and not vice versa. Other subsets may be: Hard determinism, MWI, Biological determinism, Theological determinism and many others.

Bell’s inequalities only seem to disprove local realism.

It rules out determinism based on local hidden variables, which could rule in one of: nonlocality, indeterminism, or superdeterminism.

It's frequently misquoted as merely disproving locality by those with a bias in favour of determinism

In addition, many scientists criticize the assumptions

There has always been a small but vociferous opposition. They are gradually losing the argument that experimental tests are flawed, because tests keep being repeated and refined, closing the alleged "loopholes".

and, in any case, they are compatible with different deterministic systems or with non-local hidden variables, so it is far from being a definitive tool to prove or disprove determinism.

Its not definitive and I didn't say it was, but it does hint that the issue is subject to empirical investigation.