Saturday, May 27, 2006

Is Quantum Indeterminacy Necessary for Free Will?

OK, I'm back from vacation and well-rested.

Writing-wise, I'm currently finishing an epistemology paper on inferential justification and skepticism. Reading-wise, I'm wrapping up Trenton Merricks' interesting book Objects and Persons, in which he defends the interesting thesis that conscious organisms are the only macrophysical objects there are. On his view, things like chairs, statues, brains, etc. don't exist. Instead, what we have is matter arranged chairwise, statuewise, brainwise, etc. Since all the causal work is done by the microphysical constituents of such 'objects', Merricks' argues that they are ontologically redundant and thus are best eliminated from ontology. But human beings cannot be eliminated, he argues, because we exercise causal powers that are not simply a function of our microphysical constituents.

What I'd like to talk about right now, however, is a tangential argument that occurs on pp. 155-159 of his book. It concerns the relation of quantum indeterminacy (QI) and libertarian free will (LF).

In the first place, it is uncontroversial that QI is not sufficient for LF. Acts that are free in the libertarian sense must be suitably under the deliberate control of the free agent, but the brute statistical randomness of microphysical processes according to QI is not tantamount to deliberate control.

In the second place, however, it has seemed to many that QI (or some other sort of physical indeterminacy) might be necessary for LF. After all, if QI were false and physical determinism were true, then how could any of our acts be free in the libertarian sense? Though he is a believer in LF, Merricks disagrees. He asks us to consider the following two arguments:
  1. Humans have no choice about the following truth: every action a human performs is entailed by what the distant past was like and the nature of the laws of nature.
  2. Humans have no choice about what the distant past was like or the nature of the laws of nature.
  3. Therefore, humans have no choice about what actions they perform.

  4. Humans have no choice about the following truth: every action a human performs supervenes on what the agent's constituent atoms do or are like.
  5. Humans have no choice about what their constituent atoms do or are like.
  6. Therefore, humans have no choice about what actions they perform.
Both arguments have the same structure, so if one is valid, then both are. The first argument is a popular argument for incompatibilism (famously dubbed the 'consequence argument' by Van Inwagen). Defenders of LF typically endorse the validity of the first argument but deny its soundness by rejecting (1). What Merricks points out that is that they also have to deny one or more of the premises of the second argument:
For if determinism precludes human freedom, then so does bottom-up metaphysics. So, given incompatibilism, human freedom requires (at least) one of the following two things. A person has some choice about what her atoms do or are like (the denial of [5]). Some of a person's actions fail to be fixed, one way or another, by atomic behaviour or features (the denial of [4]). If we have either, quantum indeterminacy ... is not needed for freedom. If we have neither, quantum indeterminacy ... won't help. As a result, quantum indeterminacy ... turns out to be irrelevant to human freedom.
I think Merricks is right. Affirming QI doesn't help the defender of LF as long as one affirms a 'bottom-up' metaphysics - one in which the mental is merely a supervenient epiphenomenon of the physical or microphysical. LF requires top-down causation in which the free agent exercises causal power that is not merely the vector-sum of his or her physical or microphysical constituents. In other words, LF requires that one deny the causal closure of the (micro)physical. But once one denies that, then whether QI is true or not at the (micro)physical level becomes irrelevant to LF because the causality exercised by free agents lies outside the scope of (micro)physical causation whether deterministic or indeterministic.


At 5/31/2006 10:14 AM, Blogger Ocham said...

>>On [Merrick's] view, things like chairs, statues, brains, etc. don't exist.

That view seems clearly false. I am sitting on a chair right now. There is another one by the wall next to the door.

At 6/02/2006 4:16 PM, Blogger Alan Rhoda said...

Hi Ocham,

Merricks would agree that his claims sound odd to "folk ontology", as he labels it. But he would insist that what you are sitting on is just bits of matter arranged chairwise and that there's no 'chair' over and over that. Otherwise, he argues, we would have two things - bits of matter arranged chairwise and, on top of that, a chair - that are co-located and causally redundant.

At 6/03/2006 10:57 AM, Blogger Ocham said...

Well then his view is wrong. The simple proof is, his view implies that there are, without qualification, no chairs. But there are chairs. Therefore his view is false.

It's not often you can state something quite as definite as this, and as true as this, where philosophy is concerned.

Besides (though it possibly weakens my first argument perhaps even to follow it up at all), if he insists that 'what I am sitting on' is bits of matter or whatnot, then what does 'what I am sitting on' denote? A chair, perhaps?

There really is no view so absurd that some philosopher hasn't ...

Best - Ockham

At 6/03/2006 11:01 AM, Blogger Tom said...

All I've ever understood a "chair" to be is so many bits of matter arranged 'chairwise' and that this 'chairwise arrangement of matter' is what I'm sitting on. What OTHER understanding of "chair" does Merricks have in mind which he wants to dispel? The Platonist's universal "chair"?


At 6/04/2006 1:12 PM, Blogger C Grace said...


Maybe it would help if you think about what is contained in your concept of chair. First there is the function of the chair. If I went out to the woods and brought back a tree stump and put it at my table to sit I would call it a chair. Second is shape. I differentiate a chair from a stool because of it's shape.

Therefore the concept 'chair' simply denotes matter used for a certain purpose that is in a certain shape.

If I am understanding Alan right the chair does not cease to exist. Its matter exists but it's 'chairness' is a function of human conception.

At 6/04/2006 5:02 PM, Blogger Don Jr. said...

On John Depoe's old blog, he has three posts on the issue that is being discussed in the comments section here, namely, the problem of material constitution. They might be of interest to some. (Note: He does not maintain this blog anymore—his new blog is here—so the links contained in his posts there will often be broken, due to incorrect URL's, and the formatting isn't the best.) He begins with "What is the Problem of Material Constitution?" Then he posts "Do Mid-sized Objects Exists?" And finally "Do Mid-sized Objects Exists Only as Representations?"

There are other paradoxes within the issue of material constitution that I don't think were mentioned in Depoe's opening post on the subject. For instance, what causes the boundary of the chair to be the boundary of the chair? Why do we say the chair stops here and the desk begins here? Sure, we can see the boundary of the chair (which might simply mean, as C Grace says, "it's 'chairness' is a function of human conception") but other than that what justification have we got for saying this collection of atoms does not constitute the chair but this collection of atoms does?

Or, say we have a pillow. What if we remove a single thread from the pillow? Is it still the same pillow? What if we remove two threads? How about all the threads? At what point does it cease being a pillow and start being a pile of threads? When one reflects on these paradoxes, and others (see Depoe's "What is the Problem of Material Constitution?" post), I think the issue becomes more apparent than perhaps one imagined. I know that was the case for me. I was in the exact same boat as Ocham and Tom until I began to reflect on the paradoxes seriously.

At 6/05/2006 12:33 AM, Blogger Ocham said...

C grace:
the concept 'chair' simply denotes matter used for a certain purpose that is in a certain shape

Not according to Merrick, or at least the version that Alan has given us. On this view, things like chairs, statues, brains, etc. don't exist. I.e. the noun 'chair' doesn't denote anything at all.

If I am understanding Alan right the chair does not cease to exist

You are not understanding him right. He said, or quoted Merrick to the effect that 'the chair' does not exist at all. That is false. I am sitting on a chair right now.

At 6/06/2006 7:58 AM, Blogger Don Jr. said...

Ocham, what makes that particular bunching of atoms a chair? The fact that you say it is? What if 0.001-percent of the chair was destroyed, would it still be a chair? What about a 1-percent? What if 90-percent of the chair was destroyed, would it still be a chair? When would it cease being a chair and simply be a pile of rubbish? What if 50-percent of the chair was destroyed and someone said it was still a chair (because it sort of still looked like one to her) but I disagreed? Is one of us actually right and the other actually wrong? Is there some transcendent realm governing chairs like there is in regards to morality. We can be right or wrong as regards morality: if someone says killing an innocent child is not wrong, then he's simply mistaken. In the realm of furniture, we can simply differ. No one is right or wrong. If you say this grouping of atoms is a chair what makes you right? If, however, you say this grouping of atoms looks like a chair to you (which simply means that to you it looks like your preconceived conception of a chair), then no one will disagree, nor can anyone disagree (if that's what it looks like to you, then that's what it looks like to you). But that is very different from saying the grouping of atoms is a chair.

What if on planet X the citizens use what we call chairs as coffee tables? What you say is a chair they say is a coffee table. Are they wrong or are we? If you want to compromise and say, "Well, it at least it looks like a chair," they'll say, "No, it looks like a coffee table." But all you would both be saying is that, as C Grace said, your conception of chair or coffee table resembles this particular bunching of atoms. If in the end that's all you're saying then no chair (or no coffee table) actually exists. All that exists, as Merricks says, is matter arranged chairwise (or coffeetablewise) or in the fashion of a particular conception one already has. So how do you know you're sitting in a chair right now? Maybe you're sitting in a coffee table.

At 6/07/2006 6:34 PM, Blogger C Grace said...

Ocham said: the noun 'chair' doesn't denote anything at all."

I worded my comment poorly. Let me try again. I would agree that the noun 'chair' does not denote anything at all. 'Chair' (the spoken or written word) signifies a concept in my mind, but I do not believe that a concept is a thing, nor do concepts exist. The concept itself allows me to identify matter according to function and shape etc., but that does not mean anything except the matter itself exists.

I don't know what Merrick's whole argument is though so I may be misunderstanding him. I need more backround on exactly what he meant by 'the matter is arranged chairwise'.

At 6/07/2006 6:53 PM, Blogger C Grace said...


Do you think QI is needed for God to manipulate the material universe without breaking His natural laws? It seems to me that without QI, God's freedom to affect the physical universe would be limited to what he could do through us. Or am I still misunderstanding the argument?

At 6/19/2006 11:30 PM, Blogger marco said...

Doesn't seem that QI would give god that much freedom to intervene: he'd sti be contrained by the macroscopic regularity that QI gives rise to.

I find it difficult to imagine what a spelling out of LF would be. Free acts would not be a function, I take it, of causal laws plus one's make-up. So that means, given a specification of the complete make-up of some agent, say one ho is deliberating over whether to do x or y, it's an open question which way he'll act until he does. But this seems to leave no room for the feeling I have that when he does act he will do so for a reason.

At 3/08/2009 1:34 PM, Blogger AM said...

Sorry. I know this is a late comment but I enjojed reading your post.

Please let me know if I have misunderstood you but I think you are saying that LF doesn't require QI as long as we don't say LF resides in the physical "wetware" of our brains.

This seems sound enough but we still have to ask how our consciosness interfaces with our physical bodies/brains - otherwise we would never be able to enact our LF. ISTM that QI would be useful at this point insofar as it represents little holes in natural causality through which spiritual reality might operate.

At 4/02/2009 10:08 AM, Blogger McGarr said...

I believe that we don't have free will but that we are jointly controled by acausal quantum events and causal events.

I wrote a short article about it you might find interesting @


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