A Brief Refutation of Physicalism (Part 5 - Conclusion)
In my last post, I provided some reasons for preferring substance dualism over physicalism. Today, I give a couple of more reasons and then conclude by commenting on some objections to substance dualism.
In addition to the split-brain thought experiment, there is another observation in favor of dualism. I have the property of being possibly disembodied, but my body does not have that same property. Therefore, I am not identical to my body. According to Leibniz’s law, which I referenced in a previous post, we must reject physicalism in favor of dualism.
Additionally, the reality of free will requires that we are more than just our bodies. If physicalism is true, our bodies, and therefore, our brains are physical objects which behave by natural laws and inputs. Such processes lead to determinism and rules out free choices. If free will is not an illusion, then I am more than a physical body and brain. I am also an immaterial mental substance which freely chooses my actions.
In conclusion, I will briefly address two objections to substance dualism.
Objection 1: Ockham’s razor states that entities should not be multiplied beyond necessity. Why should one posit two substances when one will do?
Answer: The key phrase in this context is beyond necessity. One substance will not do. The explanatory power and scope of physicalism is far weaker than that of dualism. Therefore, according to Ockham, we should favor two entities rather than one.
Objection 2: The mind-body interaction problem. We have no understanding of how an immaterial and a material substance can interact, therefore they cannot interact.
Answer: This objection commits the fallacy of an argument from ignorance, arguing that because one is ignorant of or cannot understand how a thing can happen it cannot happen. If one requires a scientific explanation of how such a thing can happen, one will be waiting for a long time. Since science only deals with the material and physical, it is, by nature, incapable of answering such a question. As with Newton’s gravitational laws, which were initially rejected by some because no known mechanism could account for action at a distance, the evidence in favor of dualism is strong and the interaction problem is not a reason to reject dualism in favor of physicalism.
(Much credit must be given to the work of J. P. Moreland for the ideas presented in this series. I would highly recommend his book, Body & Soul, for anyone with further interest in this subject. He also has recently published a book on a related topic, Consciousness and the Existence of God, which, although not primarily addressing substance dualism, does provide further food for thought. I am presently working my way through this book.)