Heisenberg's Uncertainty Principle

[Eternal]

There's been a discussion lately on the forum regarding Free Will. I have to admit, as a person who's just starting to learn about Objectivism, I was torn between two positions.

On one hand, I can see that Free Will seems to be self-evident. I can do whatever I please this very moment.

On the other hand, I know that if I have a physical system, given its initial state, and forces acting upon it, I can accurately predict it's final state. Why would calculating a trajectory of a ball, be different from predicting the current state of the Universe just by knowing the initial conditions present during the Big Bang. Sure - the magnitude of required calculations would be enormous, but the underlying physical laws remain the same. And since the Universe includes human minds, by the same argument, we would have as much Free Will as the ball trying to influence it's trajectory - that is: None. Again, the complexity of our "trajectories" is much greater than that of a ball, but the principle behind its predictability remains the same.

I am always very wary of accepting arguments based solely on "self-evidence". For some reason, it reminds me of religious fundies, claiming that God is self-evident. That is one of the reasons I try question the 'dogmas' of any walk of life. There is a reason for everything, and if Free Will is indeed true, as self-evidence would seem to indicate, then there must be a physical explanation behind it. I am willing to accept it as a self-evident law, but deep in my mind I'll feel like I may be cheating my reason that way.

Here is my take on why Free Will doesn't contradict physical laws of the universe. From college physics I remember Heisenberg's Principle, stating something to the effect that you cannot simultaneously know the exact momentum and position of a given object. This is true for all objects, but the smaller the object, the more apparent it becomes. This would mean two things:

1. You will never be able to predict exact final output of the system, because you can never be given its exact initial conditions.
   
2. Smallest particles (electrons/quarks and whatever physicists came up with next) in particular, contribute to our minds' Free Will by the virtue of their unpredictability. Unpredictability that is not due to randomness or deficiency of measurment instrumentation, but is part of the physical laws governing the Universe.
   

[entripon]

If you can't predict the outcome of a deterministic system (because of HUP or lack of data or other measurement problems) it's still a deterministic system. If human beings were a deterministic system, then we would indeed have no free will. However, it is by no means axiomatic that all entities in the universe are governed by "billiard-ball" style deterministic causation, which is the false premise held by individuals who don't believe in free will.

To quote Peikoff from OPAR (p. 68),

The law of causality affirms a necessary connection between entities and their actions. It does not, however, specify any particular kind of entity or of action. The law does not say that only mechanistic relationships can occur, the kind that apply when one billiard ball strikes another; this is one common form of causation, but it does not preempt the field... [The law of causality]tells us only that whatever kinds of entities there are, they act in accordance with their nature, and whatever actions there are, they are performed and determined by the entity which acts.

Determinism is not an axiom; it is an induction from countless instances in the universe where entities act in a predictable, linear progression, one event following after another in a causal chain. The problem is that determinists try to over-extend the reach of this principle: it is true of rocks and trees and clocks, so it must be true of human beings, right? Not necessarily, and indeed we can observe directly that that is not the case. The identities of rocks and trees dictate that they act in a deterministic fashion, while the identity of a human being dictates that he must make choices. There is no contradiction and no violation of "physical laws" (which are simply human inductions about what we observe happening in the universe).

We see directly that we have the ability to choose, and no later "discovery" of science can undermine that fact, since all knowledge is dependent upon it.

Edited December 11, 2005 by entripon

[Eternal]

Determinism is not an axiom; it is an induction from countless instances in the universe

I still don't like the idea of accepting something as fact, just because it happened correctly countless times. During one of my Chemistry classes, I remember the professor stating that it is possible for a man to walk through the wall, though the probability of that happening is infinitesimal (something about frequencies of the two objects having to line up, and the fact that atoms take up very little space). So just because you can try 10000000000000000000 times to walk through the wall, only to hurt yourself, doesn't mean that you won't succeed on the 10000000000000000001th time. I guess I'm looking for some elegant 'mathematical' proof, but until it comes (if ever), I'll have to settle for the old 'self-evidence'.

We see directly that we have the ability to choose, and no later "discovery" of science can undermine that fact, since all knowledge is dependent upon it.

I am looking for science to support the fact, not undermine it.

Edited December 11, 2005 by Eternal

[entripon]

I guess I'm looking for some elegant 'mathematical' proof, but until it comes (if ever), I'll have to settle for the old 'self-evidence'.

I recently took Leonard Peikoff's online course, "Objectivism Through Induction", where he attempts to dispel this mindset (which I have been guilty of many times). Looking for a logical deduction for every point rather than looking for an induction based on your experience is called 'rationalism', and it's a very bad (but very common) way to think. The evidence of your senses is more powerful than any argument; until you see the truth of a philosophic point, it will never be real to you.

I am looking for science to support the fact, not undermine it.

That's fine. Once you accept free will you can go about looking for how it emerges (why, under what conditions, etc.), but deducing it from some aspect of determinism is definitely not the way to go.

Edited December 11, 2005 by entripon

[Eternal]

I recently took Leonard Peikoff's online course, "Objectivism Through Induction", where he attempts to dispel this mindset (which I have been guilty of many times).

I'll definitely try to look into that.

[Hal]

Quantum physics approximates classical physics as things get bigger and bigger. Neurons are huge (comparatively speaking), and as such its highly unlikely that they would be affected by quantum effects. The 'uncertainty' in the uncertainty principle is normally tiny (we're talking multiples of h-bar, which is around 10^-34), and not being able to get this degree of precision almost certainly wouldnt matter unless we were dealing with tiny tiny particles (ie not neurons).

Edited December 12, 2005 by Hal

[Liriodendron Tulipifera]

Quantum physics approximates classical physics as things get bigger and bigger. Neurons are huge (comparatively speaking), and as such its highly unlikely that they would be affected by quantum effects. The 'uncertainty' in the uncertainty principle is normally tiny (we're talking multiples of h-bar, which is around 10^-34), and not being able to get this degree of precision almost certainly wouldnt matter unless we were dealing with tiny tiny particles (ie not neurons).

Exactly. We no more need Heisenberg's uncertainty principle to understand free will than we need to be titanium metallurgists or wood products engineers to understand baseball.

I think what the "determinism" people on the forum are trying to get at is that there is a physical basis to life, and since matter is predictable, so is human behavior because, ultimately, we can all be reduced to matter. Am I right in this assessment that this is the crux of the argument?

[Hal]

I think what the "determinism" people on the forum are trying to get at is that there is a physical basis to life, and since matter is predictable, so is human behavior because, ultimately, we can all be reduced to matter. Am I right in this assessment that this is the crux of the argument?

Yes I think that this is the argument that makes most people in the determinism camp abandon free-will. The most clear philosophical formulation of this is Jaegwon Kim's Supervenience Argument (warning: large amounts of academic jargon), which I dont think anyone has managed to conclusively refute yet.

To translate the above into English: assume that mental (conscious) events are correlated to physical (brain) states, ie everything that I experience corresponds to some distinct state of neurons in my brain. This seems a reasonable hypothesis unless we want to say that consciousness is magical. Now assume that the physical world is 'closed'. By 'closed', I mean that every physical event (such as a particle moving in a certain way) has a determinist and purely physical cause (such as it interacting with another particle). Again, this seems like a reasonable assumption in order for physics to be possible. If we cant explain all physical events in terms of other physical event,s then we need to postulate that non-physical things are somehow throwing atoms around in the world and explain how this is the case (the problem of Cartesian dualism).

Now, assume that I 'choose' to perform some action such as raising my arm. By the first above assumption, there is some mental state in my brain that corresponds to me making this choice - ie some particular configuration of neurons must be correlated with my mental act, unless consciousness is somehow 'hanging in the air', indepedent of the physical world. But now by our second assumption, this neuronal configuration was caused and determined by the previous neuronal configuration present in my brain 5 seconds beforehand. Assuming that neurons obey deterministic laws, then it was is physically impossible for this neuronal configuration not to have occured given the state of my brain 5 seconds earlier - my brain is a physical system that evolves in time according to physical laws, just like any other. If you disagree with this then you are claiming that the physical world is non-deterministic, and that consciousness is somehow throwing atoms around in your brain.

Now, given that this physical event (the neuronal configuration) was caused and determined by another physical event, and given that your 'choice' to raise your arm is necessarily correlated with that physical (neuronal) event, it is simply wrong to say that your arm "couldnt" have went up. That neuronal configuartion HAD to arise given the state of your brain 5 seconds earlier, and because that configuration correlates with your choosing, your choice was similarly determined.

I essentially agree with this argument, and i dont think anyone has managed to refute it (I dont see how it can be refuted either). However, I dont think its obviously true that the physical world is closed or deterministic, or that mental events and neural processes correlate exactly. I would say that these are open scientific questions which could be decided either way, hence the question of free-will is puerly scientific rather than philosophical and we simply dont know enough about the human brain to comment yet (although assuming that free-will exists is a good working hypothesis in the absence of conclusive contradictory evidence).

On a sidenote, Objectivism is strongly committed to the idea of physical determinism (observe the strong objections to Copenhagenist QM. This is one of the areas where I disagree with AR/Peikoff). But as a consequences, Objectivists now need to deny either that conscious events and brain states are correlated, or that genuine (non-compatabilist) free will exists. You simply cannot have physical determinism, correlation of physical and mental events, and true volition - they are a mutually inconsistent set as Kim's argument shows.

Edited December 13, 2005 by Hal

[Quantum Mechanic]

John Conway, a brilliant mathematician based out of Princeton, has forwarded a theory that free will is a consequence of quantum uncertainty.

Doesn't make it a correct theory mind you, but interesting and topical nonetheless.

[Liriodendron Tulipifera]

John Conway, a brilliant mathematician based out of Princeton, has forwarded a theory that free will is a consequence of quantum uncertainty.

Doesn't make it a correct theory mind you, but interesting and topical nonetheless.

Hm! Can you tell us more?

[Eternal]

John Conway, a brilliant mathematician based out of Princeton, has forwarded a theory that free will is a consequence of quantum uncertainty.

This is a page I found that attempts to explain his theory.

I like the quote at the beginning:

We must believe in free will. We have no choice. -- Isaac B. Singer

The 'uncertainty' in the uncertainty principle is normally tiny (we're talking multiples of h-bar, which is around 10^-34), and not being able to get this degree of precision almost certainly wouldnt matter unless we were dealing with tiny tiny particles (ie not neurons).

Even the tiniest of the changes, can eventually snowball into an avalanche. You know what they say about butterflies causing hurricanes...

I do remember reading something about a theory claiming that the mind is a quantum machine, that's capable of influencing the otherwise undeterminable outcome of a particle.

I do want to accept 'free will' as a fact, because otherwise life would seem pretty pointless. I haven't read an argument yet that's convinced me, but I found that I can accept the 'free will' based on one of those theories - who's to say one of them is not true.