Wednesday, November 02, 2005

On the concept of physicalism

Another update from an old post, because getting clear on the concept of physicalism is important to some previous discussion.

Physicalism, as understood in my book (and the definition is laid out clearly) is committed to three fundamental doctrines. 1) Physics is mechanistic at the most basic level of analysis. Whetever is happening to the basic stuff of the universe is fully determined by the laws of physics, the initial conditions, and perhaps a quantum chance factor. 2) Physics is closed. No physical event has a nonphysical cause. 3) Whatever exists in space and time that is not physical supervenes on the physical. Given the state of the physical, whatever states that are not physical must be the way they are and not some other way. So, for example, we can describe the braking system of a car in physical terms that does not mention the capability of stopping a car, but given the state of the physical, the braking capacities of the system are guaranteed to be there. Nothing in this definition requires reductionism, and this definition should encompass all forms of materialism, whether they are eliminative, reductive, or non-reductive. Is this definition of physicalism in any way a straw man?

4 comments:

Blue Devil Knight said...

I don't think lack of consensus is necessarily a weakness. I'd like to see 100 randomly chosen theistic philosophers who have a consensus on the concept of God. That, by itself, wouldn't show that theism is a dumb position.

As for the definition:
1) Physics is mechanistic at the most basic level of analysis. Whetever is happening to the basic stuff of the universe is fully determined by the laws of physics, the initial conditions, and perhaps a quantum chance factor. 2) Physics is closed. No physical event has a nonphysical cause. 3) Whatever exists in space and time that is not physical supervenes on the physical.

As the definition stands, you could be a physicalist and believe in goblins that don't interact with the physical or don't exist in space and time. You need something like 4) There exist no events that do not supervene on the physical.

Victor Reppert said...

So my definition is deficient because it leaves open the possibility of non-spatio-temporal goblins?

Blue Devil Knight said...

The definition leaves out the most important aspect of physicalism: the claim that that's all there is. You have provided useful criteria, but they don't go quite far enough (it is a diamond, as opposed to straw, man) in expressing our view. For instance, I could believe in nonspatiotemporal mathematical objects that do not causally interact with the physical world but still be a physicalist according to your definition. Also, I could believe in a pre-established harmony between the physical and mental. That is, the physical is causally closed, everything in space and time is physical, but there is a psychophysical parallelism with no interactions allowed.

I think you need a "and there's nothing else" clause.

You shouldn't let we physicalists sneak out of having to deal with abstract-seeming properties like the property of being an odd number.

Blue Devil Knight said...

Mike, nonphysicalism is more broad than that. Many physicalists take it that present physics/neuroscience is probably wrong, but will get it right someday, and when they do the laws will describe how things are.

My understanding of nonnaturalists of the sort on this blog (i.e., Christian) is that they want some aspects of the human condition to fall outside the sphere of what natural science says is nomically possible. ('Nomically possible' roughly means things that are possible given the theories of natural science: e.g., gravity). Even if physics expands, that just introduces a bunch of new nomic possibilities, but most dualists would say that what they want is that the human mind/soul does not "follow the laws of physics" even if the laws are expanded to include stochastic and nonlocal interactions. I don't mean to focus on physics, but fill in any natural science, e.g., neuroscience.

I'm sure others on the list have more sophisticated understanding of non-naturalism. I describe it as an outsider.