The Ghost In The Machine

David Chalmers has attained a degree of celebrity and earned the adoration of theists, with his philosophical argument against physicalism.  The argument is based on the conceivability of philosophical zombies (or p-zombies).  Before I get into the argument itself, I should explain what a p-zombie is.  This is not the fictional creature of movies that has returned from the dead, but rather a philosophical concept of something that is physically and behaviorally identical in every respect to a person, but that nevertheless lacks any conscious experience.  A p-zombie can't be distinguished from an ordinary person, because it behaves the same, reacts the same, and gives the same answers to any questions.  It would recoil from pain and say "ouch", for example, but not actually experience the feeling pain.  Another way of saying this is that the p-zombie has no subjective or first-person experience.

The Fortress of Belief

I've been arguing with Joe Hinman on the topic of my previous post.  The issue at hand was the accusation that atheists employ "God of the Gaps" reasoning, as espoused by Mikey at Shadow to Light.  I concluded that Mikey's assertion is just a case of "I know you are but what am I?"  My major point is that if a naturalist becomes convinced that God is real, it would be because of undeniable evidence that can't be explained by naturalism.  God of the Gaps belief, on the other hand, relies on a lack of evidence.  It simply assumes that God is the default explanation for anything where a full scientific explanation is lacking.  There doesn't have to be any evidence of supernatural phenomena (and in fact there isn't) to support God of the Gaps belief.

Hinman has taken issue with much of what I had to say about this topic.  To respond in detail to what I said, he has made a post of his own in one of his many blogs, called Atheistwatch.  I would like to answer all of the points he raises, but his posts are so long and rambling, lacking in cogency, and filled with fallacies and misunderstandings, that it is impractical for me to address them all.  I could spend all week trying, but I have a life.  So I'll limit myself to some of the most salient points that he makes.

The Hard Problem of Consciousness

Philosophers who favor a supernatural or dualistic view of mind have contrived an argument that they think poses a major obstacle to physicalism.  It is the so-called hard problem of consciousness, that claims there is an unbridgable gap between physical substance and mental substance.  It is basically the claim that the stuff of conscious experience - the qualia, or qualitative component of consciousness - the texture of our perceptions - cannot be explained in terms of physical substances and phenomena.  But this is an unscientific argument.  It amounts to an argument from ignorance.  It is saying that because we don't yet know how to fully explain consciousness in terms of physical matter and its properties, then there must be something immaterial about it.  This fallacy gives courage to those (especially theists) who choose to ignore the track record of naturalistic science, and instead posit the existence of things like the immaterial soul as the answer to the problem.

Misunderstanding Hume

David Hume is well-known as a materialist and empiricist.  It is inconceivable that he would think of physical objects as being products of the mind.  He viewed objects as being composed of their parts.  But if an object composed of parts is seen as an entity in its own right, that is a perception of the mind.

The WHOLE, you say, wants a cause. I answer, that the uniting of these parts into a whole, like the uniting of several distinct counties into one kingdom, or several distinct members into one body, is performed merely by an arbitrary act of mind, and has no influence on the nature of things. Did I show you the particular cause of each individual in a collection of twenty particles of matter, I should think it very unreasonable, should you afterwards ask me, what was the cause of the whole twenty. This is sufficiently explained in explaining the cause of the parts. - Hume, Dialogues Concerning Natural Religion

What does this mean?  Hume is saying that the mind has no influence on the things that are assembled into a group, but the mind perceives this assemblage as a whole object.  There need not be any explanation for the object beyond explaining the parts that constitute the whole.  He once famously said, "I am nothing but a bundle of perceptions".

How surprising, then, to see Victor Reppert use this passage as evidence for his supernatural view of mind.

An Irrational View of Naturalism

Reppert says:

My concept of what is required for naturalism is as follows:

1. The base level, whether we call it natural, material, or physical, is causally closed.
2. Everything above that level supervenes on the physical/material/natural.
3. Physics is mechanistic. The base level lacks intentionality, purpose, normativity, and subjectivity.

In Victor's view either naturalism doesn't explain everything that exists, or naturalism must be extended to include more than the physical.