Philosophy of mind is not something I’ve studied very much, but I do know about the different views like physicalism, epiphenomenalism, property dualism and substance dualism. I also know some of the basic arguments for and against each view.

In this post, I just wanted to show people a little bit about how you argue for substance dualism, using philosophical and scientific arguments. I find this topic to be really really dry, and I can barely stay awake when J.P. Moreland talks about it in lectures. But I hope a little bit of exposure won’t put you all to sleep.

Philosophical arguments

Let’s start with this old paper by John Depoe.

He writes about the persistent identity argument:

Another argument supporting substance dualism is that one maintains personal identity through change. Even though one is continuously going through physical changes and experiencing different mental states, a person continues to be the same person. If persons were identical with their physical parts or mental states, they would cease to be the same persons as these changes occurred. Therefore, it is necessary to postulate an immaterial, substantial self that endures through change.

Suppose that someone believes that people do not maintain identity through change and concludes that the previous argument for substance dualism fails. This denial of personal identity through change, I contend, presents untenable difficulties. First, there is one’s own awareness of being the same person through change. Moreover, if one is not literally the same person through these changes, how can a person maintain long-term goals and desires?

If you are your body, and your body is always changing, then you aren’t the same person now as 5 minutes ago.

There are more arguments for substance dualism here, from J.P. Moreland.

Experimental evidence

Doug Groothuis talks about some experimental evidence in this paper.

Excerpt:

Dr. Wilder Penfield was known for his ground-breaking work with epilepsy. His work involved stimulating brain tissue in conscious patients in order to find the causes of epilepsy. During these sessions Penfield found that the prodding of certain areas of the brain triggered vivid memories of past events. The patients reported remembering clearly such things as the taste of coffee. One patient, while on an operating table in Montreal, Canada, remembered laughing with cousins on a farm in South Africa. What amazed Penfield was that his patients, who were not under anesthetic, were simultaneously conscious of the re-experienced memories and of being prodded by an electrode in an operating room. Penfield called this a “double consciousness” wherein a memory was stimulated physically but was attended to and recognized as a memory by a conscious patient. Penfield likened this to the patient watching a television program while remaining aware that it wasn’t now happening.

Penfield repeated these results on hundreds of epileptic patients and concluded that a separable mind was able to track what the brain was doing as a result of the artificial stimulation. One’s mind in a sense could transcend the operations of the brain, monitoring memories without actually placing oneself in the situation remembered. Penfield noted that “The mind of the patient was as independent of the reflex action as was the mind of the surgeon who listened and strove to understand. Thus, my argument favours independence of mind-action.” Penfield also stated that if we liken the brain to a computer, it is not that we are a computer, but that we have a computer.

Penfield, who began his research as a materialist, switched to dualism after extensive research with epileptic patients. He said, “Something else finds its dwelling place between the sensory complex and the motor mechanism. . . . There is a switchboard operator as well as a switchboard.”

Although nonepileptic patients do not respond similarly to brain stimulation, other researchers, such as Sir John Eccles, a neurobiologist, have similarly concluded that the brain alone cannot account for a many phenomena. Eccles’ hypothesis is that the self-conscious mind is an independent entity that is actively engaged in reading from the multitude of active centres in the modules of the liaison areas of the dominant cerebral hemisphere. The self-conscious mind selects from these centres in accord with its attention and its interests and integrates its selection to give unity of conscious experience from moment to moment.

Thus, Eccles’ conclusions agree with Penfield’s, and his areas of research extend farther than that of epileptic patients. Eccles deems the “monist materialist” hope for an eventual physical explanation for mental events as wrongheaded in principle because mental events are not “simply derivative of aspects of nerve endings. There is no evidence for this whatever.” Further, Eccles argues that his “strong dualist-interactionist hypothesis . . . has the recommendation of its great explanatory power. It gives in principle at least explanations of the whole range of problems relating to brain-mind interaction.”Eccles notes that it has been impossible to develop a materialist explanation of “how a diversity of brain events come to be synthesized so that there is a unified conscious experience of a global or gestalt character.” Given this impasse, Eccles proposed that “the self-conscious mind” serve to integrate the apparently disparate brain processes into a unified consciousness.

I think that Alvin Plantinga, Keith Yandell, J.P. Moreland, William Lane Craig, Stephen Davis, John Depoe, Douglas Groothuis and Charles Taliaferro all defend substance dualism. I’m a substance dualist, myself.

What’s the objection to substance dualism?

The big objection to substance-dualism is the problem of how you get the non-physical substance to interact with the physical substance. It’s like how people put forward the grounding objection when talking about middle knowledge and where God’s knowledge of counterfactuals of creaturely freedom comes from. I wonder if anyone can post a comment for me to point me to a resource on answering the interaction problem in the comments.

UPDATE: One of my elite special forces ninja commenters writes:

Here’s Ed Feser on the Interaction Problem:

http://edwardfeser.blogspot.com/2008/10/interaction-problem.html

and

http://edwardfeser.blogspot.com/2009/04/interaction-problem-part-ii.html

The thrust of his argument is that, if the soul is the extension of the body’s “form” without matter, then it interacts with the more material parts of us in the same way that forms in general interact with matter- this approach involves rethinking our metaphysical understanding of matter, rather than coming up with a clever idea of the soul, and it does get rather involved in Thomistic metaphysics, but I think it’s pretty interesting.