In his Meditations on First Philosophy, Rene Descartes attempts to discover a foundational belief that is one hundred percent certain. He does this in order to establish a standard to which everything else could be measured. Through radical skepticism, Descartes is able to find one justified, true belief: I exist as a thinking thing, or, “I exist, therefore I am.” This states that the only true knowledge one can have is the knowledge of one’s own consciousness. This consciousness is commonly referred to as the mind. The mind is the “thinking thing” that is capable of thought, houses a person’s personality, and is responsible for emotions. Beyond these abstract characteristics, however, it is not entirely clear what the mind is. Is the mind simply a conscious or is it in fact a physical entity? Rather than a separate entity, is the mind actually a part of the body? Questions such as these give rise to the mind-body problem—a philosophical debate regarding the relationship between the mind and the body. Two of the most prominent solutions to this debate are substance dualism and physicalism. I will argue that substance dualism is the more logical solution to the mind-body problem. Like Descartes, I believe that it is superior because it provides reasonable explanations for what we experience in the world.
The mind is most commonly referred to as one’s own consciousness. It is the thing that has mental states, sensory perceptions, and is capable of making decisions. The body is the physical piece of organic matter that we are able to sense. For this argument, we will refer to the brain as being a physical part of the body. One way to distinguish the brain from the mind is to imagine the brain as the physical container for the mental workings within it—aka the mind. In other words, the brain acts like a computer while the minds acts like the software programmed into the computer. It is evident that the mind and the body have a tight connection with one another; they can interact and influence each other. However, Descartes concludes that the mind is completely separate from the body.
This belief—that the mind and the body are two distinct entities—is central to the idea of substance dualism. It is the claim that all objects in the universe fall into one of two separate categories: physical objects or nonphysical minds. For example, a chair or a cookie would be categorized as a physical object; emotions or the concept of God would fall into the nonphysical mind category. Substance dualism states that the body is a physical object while the mind in nonphysical. The mind cannot be physical because the conscious does not have physical properties. It is impossible to extract the mind and tangibly observe its contents. One could not take the mind and physically weigh out its inner thoughts; however, one could weigh the physical brain and give it a numerical value. Furthermore, the nonphysical mind does not have the same characteristics of this physical world. For example, the nonphysical mind is capable of irrational thoughts: delusional thinking, catastrophizing, etc. However, it would be illogical to say that the physical body has irrational hormones circulating through its bloodstream. For these reasons, it is evident that the mind and the body cannot be one and the same. Therefore, if the body is physical then the mind must be nonphysical.
Substance dualism is contrasted with the idea of physicalism. It is the idea that the universe is composed solely of physical things; thus, every mental state is identical to some physical state within the brain. Princess Elisabeth uses the physics of motion to support this idea and counter Descartes’ claim of substance dualism. The physics of motion states that a physical object cannot be moved unless another physical object exerts force on it. The vast majority of people accept that the mind controls the body. According to this theory, then, the mind must be a physical object because a nonphysical object cannot cause the motion of a physical one. Furthermore, science provides support for the idea of physicalism. With scientific advances, people are increasingly able to explain phenomena that Descartes would classify as nonphysical: memory, emotion, and other operations of the mind. However, science is defined as the practical study of the behavior of the physical world. If this is the case, does that not confirm that operations of the mind are physical? Therefore, according to physicalism, the mind and the body do not actually fall into two separate categories. They can both be classified as physical objects.
I respond to such counter arguments by first acknowledging that the mind is in fact connected to the body. They interact and influence each other; however, they are not one and the same. It is unreasonable to try to understand the mind simply in relation to the physical body. When science draws conclusions about the operations of the mind, it is based on physical evidence. For example, a scientist releases research on human emotion. This research was founded after studying the physical brain structure or the physical impulses that run through the nervous system. These observations were then used to draw conclusions about the mind. Thus, the scientist did not actually study a physical mind. Furthermore, the mind and the body are separate because scientists only have access to the body (or brain). Scientists cannot physically access the thoughts, beliefs, and emotions that are within the mind. While the physical body can communicate workings of the mind, these workings cannot be inherently known by others.
For these reasons, I agree that substance dualism is the more logical solution to the mind-body problem. Substance dualism gives power to the human mind because it regards its unique potential; it does not limit the mind to only being a part of the body. Therefore, it is more practical to view the physical body and nonphysical mind as separate rather than the same.