# Free Will versus Determinism **URL:** \ **Category:** In My Humble Opinion\ **Created:** [June 6, 2025, 8:19pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278 "2025-06-06T20:19:35Z")\ **Posts on this page:** 20\ **Page:** 4
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [June 8, 2025, 7:53am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/61 "2025-06-08T07:53:54Z")
If it is not random, nor is it determined, that sounds exactly like a combination, something in between. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 7:57am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/62 "2025-06-08T07:57:47Z")
No; what it is, is nonsensical. That’s one of the classic criticisms of free will: that the idea of something _neither_ determined nor random simply makes no sense. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 8:01am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/63 "2025-06-08T08:01:42Z")
> [@Der\_Trihs](#): > > No; free will is supposed to be neither random nor determined. Which, as I have explained, is going to look like randomness from the perspective of any theoretical model, since the postulate of randomness is the only way an otherwise information-preserving system can account for the creation of new information. I mean, you could equally well postulate that any apparently ‘random’ event is produced by the free will of god, yielding a certain sort of occasionalism! Really, the label you put onto the non-determinist events is arbitrary—so maybe one should just call them non-determinist, which unveils the vacuousness of the statement: everything is either determinist or non-determinist. That the non-determinist events are produced in some impersonal way, by the universe throwing dice, is then an additional, and unsupported, hypothesis. They may just as well be instances of agent causation. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 8:08am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/64 "2025-06-08T08:08:04Z")
> [@Der\_Trihs](#): > > That’s one of the classic criticisms of free will: that the idea of something _neither_ determined nor random simply makes no sense. Something neither determined nor non-determined wouldn’t make sense; but equating non-determined with randomness—in the sense of some impersonal force somehow choosing an outcome from a probability distribution—is too quick. A universe with Zeno machines would, for any ordinary machine, look like a universe with randomness; but it doesn’t thereby follow that the outputs of such a machine are just random throws of the dice. It’s just saying that a Turing machine can’t model a Zeno machine. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 8:08am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/65 "2025-06-08T08:08:42Z")
> [@Half\_Man\_Half\_Wit](#): > > Which, as I have explained, is going to look like randomness from the perspective of any theoretical model, since the postulate of randomness is the only way an otherwise information-preserving system can account for the creation of new information. No, it won’t. Randomness has a specific mathematical definition; which is uncertainty, not “new information”. Nor would free will create new information, it would just render whatever information it interacted with useless due to its erasure of cause and effect. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 8:13am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/66 "2025-06-08T08:13:50Z")
> [@Der\_Trihs](#): > > No, it won’t. Randomness has a specific mathematical definition; which is uncertainty, not “new information”. No, uncertainty isn’t randomness in the mathematical sense. Mathematically, the simplest definition is incompressibility, which is indeed equivalent to saying that it isn’t reducible to any finite [amount of information](https://en.wikipedia.org/wiki/Algorithmically_random_sequence)—any further bit adds new information not reducible to previous information. > [@Der\_Trihs](#): > > Nor would free will create new information, it would just render whatever information it interacted with useless due to its erasure of cause and effect. Any free act would be an act not deducible from prior information, that is, there is no reversible transformation from the state prior to the free act to the state after; which is the definition of creating new information (it’s in this sense, for instance, that unitary quantum evolution is usually said to preserve information). These aren’t my ideas—they’re fairly standard mathematical notions. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 8:25am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/67 "2025-06-08T08:25:49Z")
Uncertainty is definitely random in the mathematical sense, that’s why quantum processes are a classic method of acquiring true random numbers. > [@Half\_Man\_Half\_Wit](#): > > Any free act would be an act not deducible from prior information, that is, there is no reversible transformation from the state prior to the free act to the state after; which is the definition of creating new information (it’s in this sense, for instance, that unitary quantum evolution is usually said to preserve information). No, it would be constantly erasing information, by violating cause and effect. Existing information would fail to continue into the future as it is continuously overwritten by magical free will. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 8:34am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/68 "2025-06-08T08:34:55Z")
> [@Der\_Trihs](#): > > Uncertainty is definitely random in the mathematical sense, that’s why quantum processes are a classic method of acquiring true random numbers. ‘Uncertainty’ in the mathematical sense usually refers to the amount of information known about a given situation, e.g. the variance or spread in the predictions of a given situation. It’s a measure of how much is known about an actual state of affairs. Randomness, on the other hand, involves information that doesn’t exist yet, that couldn’t even be predicted from having perfect knowledge, because there is no possible algorithm that takes the information up to a given point in time, and computes future information from that. > [@Der\_Trihs](#): > > No, it would be constantly erasing information, by violating cause and effect. Existing information would fail to continue into the future as it is continuously overwritten by magical free will. Again, that is simply false. Typically, the full set of causes of a given event—everything that happened in the past light cone—underdetermines which event takes place. That one out of the possibilities is being realized—whether randomly or by agent causation—then adds information without invalidating any prior information. It’s as in chess: the full history up to a given position doesn’t determine the next move uniquely. Choosing one of the possible moves, however, in no way does anything to erase that history—all of the information from the prior moves is still as efficacious in determining the future moves as it used to be. Anyway, it’s clear you have no interest in really interrogating your assumptions here. For the record, again, these aren’t even controversial—they’re what I take to be the standard mathematical definitions, at least as I know them from my own work (which is, without trying to pull rank or anything, as a theoretical physicist specializing in quantum information theory). ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 8:48am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/69 "2025-06-08T08:48:22Z")
> [@Half\_Man\_Half\_Wit](#): > > Typically, the full set of causes of a given event—everything that happened in the past light cone—underdetermines which event takes place. That one out of the possibilities is being realized—whether randomly or by agent causation—then adds information without invalidating any prior information. It’s as in chess: the full history up to a given position doesn’t determine the next move uniquely. Choosing one of the possible moves, however, in no way does anything to erase that history—all of the information from the prior moves is still as efficacious in determining the future moves as it used to be. That’s because free will _isn’t_ a real thing. You are describing determinism - even using the _word_ “determines” - not free will. Under free will the past doesn’t affect the future, nothing can be predicted, and cause and effect do not hold. But people don’t like the implications of that so they tend to try to label determinism as free will, while pretending it isn’t determinism. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 8:53am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/70 "2025-06-08T08:53:05Z")
> [@Der\_Trihs](#): > > Under free will the past doesn’t affect the future, nothing can be predicted, and cause and effect do not hold. Again, simply false. In a universe with free will, cause and effect is as efficacious as in a universe with (some) randomness. It just means that on certain occasions, where causal relations don’t uniquely settle the future state of the world, this state is brought about by an agent, rather than by a throw of the dice. Otherwise, on a descriptive level, there is no difference. But people don’t like the implications of that so prefer to label free will as randomness, so they don’t have to face the possibility of being accountable for their choices. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 9:00am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/71 "2025-06-08T09:00:59Z")
> [@Half\_Man\_Half\_Wit](#): > > In a universe with free will, cause and effect is as efficacious as in a universe with (some) randomness. It just means that on certain occasions, where causal relations don’t uniquely settle the future state of the world, this state is brought about by an agent, rather than by a throw of the dice. In other words, magic. You might as well just use some mystical term like “soul” instead of “agent”. It’s all about the idea that _Humans Are Special_ and above the laws of physics. Or logic. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 9:34am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/72 "2025-06-08T09:34:26Z")
> [@Der\_Trihs](#): > > In other words, magic. You might as well just use some mystical term like “soul” instead of “agent”. It’s all about the idea that _Humans Are Special_ and above the laws of physics. Or logic. Just as ‘magic’ as the creation of the world out of nothing, or its infinite existence for no further reason, or the occurrence of random events (which is just more ex nihilo), or indeed, causation or the laws of physics somehow guiding events: everywhere, we bump into the Münchhausen trilemma once we try to interrogate these further. It’s only your predilections that make you interpret this as an argument against free will while refusing to turn this same skepticism towards the black boxes you have chosen to accept. This is a consequence of logic applied consistently; it’s the distinction between these that is fundamentally illogical, and cheap rhetoric changes nothing about that. ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [June 8, 2025, 10:39am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/73 "2025-06-08T10:39:14Z")
> [@Voyager](#): > > Maybe we can define a free will metric. By that metric the restaurant patron has more free will than the prisoner, who has more than an AI. The metric would have to be multidimensional with weighting required to come up with a final number. (And philosophers can have fun arguing about what the weights should be.) We can come up with metrics for how free our choices are in a particular situations. Just like there are chess positions where there’s very little action right now and you’re free to make a fresh plan, versus positions where there are clear threats that you must respond to, versus a situation where there is only one legal move. But this is not “free will”. Looking for some kind of metric of _free will_ seems to me like looks for some metric of [vitalism](https://en.wikipedia.org/wiki/Vitalism). It’s just muddying the waters for no explanatory gain. Step 1 needs to be defining free will concretely enough that we can at least talk about the differences between a universe with it versus without it. I don’t think we’ve reached that step, in either this thread or any of the others that went for hundreds of posts. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [June 8, 2025, 11:06am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/74 "2025-06-08T11:06:26Z")
Life is a series of rooms and doors, you are free to chose any of them, or even break through walls, stay back, invent whatever you want. There is a pattern one may learn that will lead out of that maze, and learning that pattern teaches you its purpose and following it is the only way out. Its purpose is not only agreeable to who we are, and ultimately is who we are. Once we make the decision to follow this pattern, we are already out and on to the next level. ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [June 8, 2025, 11:30am UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/75 "2025-06-08T11:30:28Z")
> [@Mijin](#): > > Step 1 needs to be defining free will concretely enough that we can at least talk about the differences between a universe with it versus without it I don’t think we’ve reached that step, in either this thread or any of the others that went for hundreds of posts. I mean, I’ve given that, and even a mechanism for it, many times before, in the Zeno machine. So far, that’s just been summarily ignored, and then the claim is repeated that nobody has ever given such a definition. But again, all that’s needed is a device that is able to set its own state by infinitely iterating over that same state—this will then be set exclusively due to its own will, i.e. not by anything exterior, while at the same time, not being random, i.e. not determined by a transcendental coin flip. Let’s look at [Strawson’s formulation](https://philosophy.as.uky.edu/sites/default/files/The%20Impossibility%20of%20Moral%20Responsibility%20-%20Galen%20Strawson.pdf) in more detail: > 1. Interested in free action, we are particularly interested in actions that are performed for a reason (as opposed to ‘reflex’ actions or mindlessly habitual actions). > 2. When one acts for a reason, what one does is a function of how one is, mentally speaking. (It is also a function of one’s height, one’s strength, one’s place and time, and so on. But the mental factors are crucial when moral responsibility is in question.) > 3. So if one is to be truly responsible for how one acts, one must be truly responsible for how one is, mentally speaking–at least in certain respects. > 4. But to be truly responsible for how one is, mentally speaking, in certain respects, one must have brought it about that one is the way one is, mentally speaking, in certain respects. And it is not merely that one must have caused oneself to be the way one is, mentally speaking. One must have consciously and explicitly chosen to be the way one is, mentally speaking, in certain respects, and one must have succeeded in bringing it about that one is that way. > 5. But one cannot really be said to choose, in a conscious, reasoned, fashion, to be the way one is mentally speaking, in any respect at all, unless one already exists, mentally speaking, already equipped with some principles of choice, ‘P1’ - preferences, values, pro-attitudes, ideals - in the light of which one chooses how to be. > 6. But then to be truly responsible, on account of having chosen to be the way one is, mentally speaking, in certain respects, one must be truly responsible for one’s having the principles of choice P1 in the light of which one chose how to be. > 7. But for this to be so one must have chosen P1, in a reasoned, conscious, intentional fashion. > 8. But for this, i.e. (7), to be so one must already have had some principles of choice P2, in the light of which one chose P1. > 9. And so on. Here we are setting out on a regress that we cannot stop. True self-determination is impossible because it requires the actual completion of an infinite series of choices of principles of choice. > 10. So true moral responsibility is impossible, because it requires true self-determination, as noted in (3). So this sets out very clearly what is necessary for free will: completing the infinite sequence of self-determinations. This the Zeno machine can do: there’s thus a clear and simple model of how free well would work. Against this, of course, one can hold that such an infinite sequence is possible. Fair enough! I think this aligns with everybody’s intuitions. But then, one is confronted with the question, as no finite sequence of instructions can create random data, how does randomness arise? Believing it does entails just the same belief in trans-finite methods. (And so does creation out of nothing, or trivially the existence of an infinite universe.) (And indeed, if one somehow has a source of randomness, then every behavior of a Zeno machine can be replicated with that and a finite algorithm, so there’s a genuine equivalence here.) So the other option is that it’s just mechanistic explanation that runs into troubles here. Theories are really just transformations of information (like computations); they can’t account for the creation of novel information, as in random events. But since there are random events, and the universe presumably has been created, maybe we need to question our intuition. But then we find that Strawson’s regress simply ceases to be a problem! Every search for ‘ultimate’ explanations eventually lands at circularity, regress, or dogma, i.e. deciding the issue by fiat. But that’s just inherent to how explanation works: it takes a pre-existing state of affairs, and deduces some resulting state by means of a finite sequence of steps. Maybe that just doesn’t capture everything going on in the world. After all, nobody has ever promised us that it does! ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [June 8, 2025, 1:37pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/76 "2025-06-08T13:37:26Z")
> [@Half\_Man\_Half\_Wit](#): > > > [@Mijin](#): > > > > Step 1 needs to be defining free will concretely enough that we can at least talk about the differences between a universe with it versus without it I don’t think we’ve reached that step, in either this thread or any of the others that went for hundreds of posts. > > I mean, I’ve given that, and even a mechanism for it, many times before, in the Zeno machine Well I said definition, not mechanism. I don’t believe we’re even talking about a meaningful concept yet. I don’t think we should be doing deep dives on the mechanism of vitalism before defining how it differs from metabolism and why we have any grounds for supposing it exists at all. Likewise with free will. I mean, I’m not trying to tell you what to do, it just seems to be putting the cart miles ahead of the horse IMHO. ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [June 8, 2025, 2:28pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/77 "2025-06-08T14:28:53Z")
> [@Der\_Trihs](#): > > One point I’ve seen made in the past is that a belief in free will is useful for the powerful and predatory to encourage, because it makes people easier to manipulate and indoctrinate. People who believe in free will are less likely to take the first step in resisting manipulation; recognizing that they are vulnerable to manipulation in the first place. I would question that because when one looks at history, movements that go against the powerful are started by people that realized that the status quo was not a good one. > **[Declaration of Independence: A Transcription](https://www.archives.gov/founding-docs/declaration-transcript)** > > Note: The following text is a transcription of the Stone Engraving of the parchment Declaration of Independence (the document on display in the Rotunda at the National Archives Museum.) The spelling and punctuation reflects the original. ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [June 8, 2025, 2:39pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/78 "2025-06-08T14:39:04Z")
> [@Der\_Trihs](#): > > No; what it is, is nonsensical. That’s one of the classic criticisms of free will: that the idea of something _neither_ determined nor random simply makes no sense. “What good is a new-born baby?” (Attributed to Benjamin Franklin, but I _decided_ to report that it is likely that it did not originate with him. 🙂 ) ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [June 8, 2025, 2:59pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/79 "2025-06-08T14:59:50Z")
> [@Mijin](#): > > But this is not “free will”. Looking for some kind of metric of _free will_ seems to me like looks for some metric of [vitalism](https://en.wikipedia.org/wiki/Vitalism). It’s just muddying the waters for no explanatory gain. I don’t see why there is a need to muddle the waters. 🙂 Again, I don’t see this issue of Free Will as an absolute, what I do see is that many times in our lives we can go from having no basic free will as babies, to gaining some wisdom when growing up (and this depends a lot on where one is born), to losing again mostly when reaching senility. In between, a lot of things: like prison, dictators or manipulating media, do take a lot of it away. Vitalism BTW is not considered a viable thing nowadays. Looking at the progress science has done, many phenomena previously attributed to a vital force have been successfully explained. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [June 8, 2025, 4:38pm UTC](https://boards.straightdope.com/t/free-will-versus-determinism/1019278/80 "2025-06-08T16:38:39Z")
> [@GIGObuster](#): > > “What good is a new-born baby?” “Free will” isn’t analogous to a newborn baby, it’s analogous to “fnord”. Something not real that isn’t even actually defined properly. [Previous page](https://boards.straightdope.com/t/free-will-versus-determinism/1019278.md?page=3) [Next page](https://boards.straightdope.com/t/free-will-versus-determinism/1019278.md?page=5)