Rene Descartes Dualism Essay

Rene Descartes was a french philosopher in the 17th century who was strict in believing more in his own self than the words of any other philosopher. Descartes dualistic theory of the mind is that the mind and the body are separate things. He believes that the body is a physical non thinking thing and the mind is a non physical thinking thing. There are two different substances Descartes believes in. There is physical substance which would be a chair, body, or clock which exist in time and space and there is mental substance like thoughts or consciousness which don’t exist in time or space. The physical substance is called res extensa and the mental substance is called res cognita.

The idea that the mind and body are two separate things is

called dualism. If dualism were to be proven that would mean that when we die, our bodies die and our minds would survive because they’re not connected. Because of this fact dualism has gained some popularity, it restores hope that there is life after death. It also brings about the idea that maybe we can replace our bodies with new ones and keep our original minds and live forever. Dualism seems fantastic at this point, but there are many arguments against it. Descartes was challenged many times with questions about his theory of dualism. To begin, if mind and body are separate then how exactly do they function together? He argued that they interact at the pineal gland which is in the limbic system in the middle of the brain. His explanation to this was that the pineal gland’s function is to take the two images perceived from the eyes and fuse them together and project the image. This meant seeing was from the soul connecting with the image projected by the pineal gland. However if this were true, how exactly does a soul see? If the soul can see what is projected on the pineal gland in your body, then there must be a soul inside your soul that can see what is projected on its pineal gland. This is considered the homunculus fallacy and it makes this argument weak. his body feels pain or hunger the body is experiencing it, not him as consciousness.
Only our soul can see what is projected on the pineal gland in our bodies, and therefore our experiences are private to ourselves. No one else can view our experiences the way we view them, and we can’t view other people’s experiences the way they view theirs. This idea is also seen in Wittgenstein's example of the beetle in the box. It states that you get a box and everyone around you has a similar box and you look in the box and all report there was a beetle inside of it. We cannot look into another person’s box and see if there is a beetle in there, there is no way to discover that answer. In the same way we cannot look into another person’s mind to find out how they experienced life and only can see through our own. If our mind and body were one, would we all have the same experiences and we all be one?
Descartes argues that if we take apart a machine we find nothing to explain how it works, and in the same way if we open up a brain and examine it we can’t find thoughts.

Therefore thoughts cannot arise from physical interaction and the mind and body are separate. If the mind and body are separate, then what is the mind made out of? Is mental substance made out of stuff that is beyond matter? Can we say if it doesn’t exists physically, does it exists at all? This is another problem faced with dualism. Maybe we can’t define what a mental substance is made out of or what exactly it is, but Descartes can explain what consciousness is. He explains consciousness by first claiming animals don’t have consciousness. He believes we shouldn’t feel suffering over killing an animal because they don’t have consciousness. How we know they don’t have it is that they can’t communicate intelligently with humans and they can’t explain their actions with knowledge. Animals cannot demonstrate adaptability in response to a new situation like a human can. This means that animals don’t contain mental substance, they are just a physical substance. From this Descartes says one can’t build a machine that can communicate with humans because machines are like animals and they cannot have consciousness. This is somewhat contradictory to dualism because there is a possibility that we could create machines that contain a human’s mental substance in them which would lead to immortality and would prove

dualism.
One of Descartes arguments to defend dualism relies on Leibniz’s law which states two things with all the same properties are the same thing; they are one. Descartes says that the mind and body have different properties therefore they are separate things. He believes that in order to find the truth we have to start out by doubting everything. The one thing he could not doubt was that the mind exists, because he can’t doubt that he is thinking and in order to have thoughts a mind must exist. This also adds to his argument that if he can doubt that the body exists but can’t doubt that the mind exists, then they must be two separate things. The problem with this argument is that in some cases Leibniz’s law does not hold true. For example Batman is a superhero who fights crime at night, and Bruce Wayne is a billionaire who owns a mansion. According to Leibniz’s law these are two different people with two different properties, therefore they are not the same person. This is wrong because we all know that Bruce Wayne the billionaire dresses up as Batman the superhero and fights crime. This proves Descartes wrong again. What one thinks of something is not a property of that thing, it is a property of oneself.
He revisits this argument when he considers God’s existence and he first thinks God controls the thoughts Descartes is having. Then he jumps to say that those thoughts must be coming from the energy of his mind so he is giving himself these thoughts. He goes further to say if he doubts he has a body and his existence is an illusion then why isn’t he persuaded that he doesn’t exist? That is because in order to be persuaded that he does not exist he has to exists in the first place. This brings Descartes to his famous saying of “I think therefore I am”.
Dualism also presents the idea that a non-physical substance can keep continuity of mind in a body that is physically changing. This is also wrong in the case where someone has brain damage. If someone has brain damage that prevents them from hearing, the non-physical substance doesn’t come into the brain and fix the hearing. If this were true, that would mean our bodies would never die because the mind would always be restoring what changes in the body which contradicts the idea of dualism because the mind and body would live on forever.
Another argument from Descartes is that only one specific soul is given to one specific human body at a time. Immanuel Kant wonders how is one individual soul differentiated from any other soul and how many souls can we know exist. What if there aren’t enough human bodies in existence for the souls to fill, do the souls just wait around for there to be more bodies? Where would they wait around, and what would they do in their spare time? Or what if there are too many human bodies and not enough souls? If one soul is given to one specific human body at a time, that must mean that when we die our soul lives on in another body. If this were true our soul would remember our old experiences from the old body it lived in and would also gain new experiences from the new body the soul lived in. At what point would we stop remembering our past experiences?