Post Author: Bill Pratt
If you recall, at the end of the series comparing physicalism and dualism, I promised to look at additional problems for physicalism. Before doing so, let me remind you what physicalists believe. Here is philosopher J. P. Moreland:
According to physicalism, a human being is merely a physical entity. The only things that exist are physical substances, properties, and events. When it comes to humans, the physical substance is the material body, especially the parts called the brain and central nervous system. The physical substance called the brain has physical properties, such as a certain weight, volume, size, electrical activity, chemical composition, and so forth.
Physicalists are usually metaphysical materialists who believe that all that exists is matter in its different forms. There is nothing immaterial that exists.
Moreland brings us to a fundamental human capacity that we all take for granted, that of free will. What do we mean by free will? Moreland explains:
When we use the term free will, we mean what is called libertarian freedom: Given choices A and B, I can literally choose to do either one. No circumstances exist that are sufficient to determine my choice. My choice is up to me, and if I do A or B, I could have done otherwise. I act as an agent who is the ultimate originator of my own actions.
Is there room for free will under physicalism? Moreland argues that there is not.
If physicalism is true, then human free will does not exist. Instead, determinism is true. If I am just a physical system, there is nothing in me that has the capacity to freely choose to do something. Material systems, at least large-scale ones, change over time in deterministic fashion according to the initial conditions of the system and the laws of chemistry and physics. A pot of water will reach a certain temperature at a given time in a way determined by the amount of water, the input of heat, and the laws of heat transfer.
There are other problems that follow if determinism is true. What about moral obligation or responsibility? What about moral praise or blame?
Now, when it comes to morality, it is hard to make sense of moral obligation and responsibility if determinism is true. They seem to presuppose freedom of the will. If I “ought” to do something, it seems to be necessary to suppose that I can do it. No one would say that I ought to jump to the top of a fifty-floor building and save a baby, or that I ought to stop the American Civil War, because I do not have the ability to do either. If physicalism is true, I do not have any genuine ability to choose my actions.
Moreland concludes with the following:
It is safe to say that physicalism requires a radical revision of our commonsense notions of freedom, moral obligation, responsibility, and punishment. On the other hand, if these commonsense notions are true, physicalism is false.