withallyourmind.net

Intentionality is defined as the “ofness” or “aboutness” of sensations, beliefs, and thoughts. Intentionality is a feature which is true of mental states, but not of physical states. Beliefs are about something, thoughts are of something, and sensations are of things. Neurons and electrical impulses are not about or of anything. One cannot say that a particular neuronal connection is “about” eating ice cream, but a thought can be about such a thing. A neurochemical process is not “about” the president of the United States, but a belief can be. As illustrated in previous posts, it is evident that there are properties held by mental states which are not true of physical states. Therefore, applying Leibniz’s law, we can see that they are not identical.

One might argue that all that has been shown so far is that there is a difference in mental properties and physical properties. This would at least establish that property dualism is true. I think there is good reason to go further and believe that substance dualism is true. It is not just that the physical brain has two kinds of properties (property dualism), but humans possess a body and an immaterial soul which possess their respective kinds of properties.

In my next post, I’ll provide some reasons for thinking this is the case.