By: Rachel Lyle, June 16th, 2017

Here is my third and final paper from Philosophy class:

Rene Decartes in his meditations on first philosophy, in Meditation VI entitled “On The Existence of Material Objects and the Real Distinction of Mind from Body” argues that dualism is true and that the mind and body are two separate entities. He uses two arguments to prove that they are separate. In one of them he uses the argument of Divisibility to prove that the mind is distinct from the body. In this paper I will prove that Descartes’ argument of divisibility, even if valid and sound, is false.

In his argument of divisibility Rene Decartes argues that dualism is true and that the mind and body are two completely distinct substances. Dualism is the position on the mind-body problem that cannot identify with the body or part of the body, or that mental properties are not physical properties. (Glossary pg. 847) The Definition of a Substance is something that is the subject of predication and capable of independent existence. (In-Class) He believes that the mind is a mental substance and the body is a physical substance. Mental Substances and physical Substances are two different things because they do not share the same properties A mental substance is immaterial, non-extended, thinking, while a physical substance is material, extended, non-thinking. (In-Class) He believes that the body is a substance that is divisible but the mind is a substance that is indivisible. This is a belief that leads to and illustrates Leibnitz’s Law. Leibnitz’s Law says that if two things are not the same thing, they do not share the same properties, also known as the non-identites of discernabees, and If two things are the same thing, then they share the same properties, also known as the identities of indiscernables. (In-Class) Therefore because the body divisible but the mind is not, they do not share the same properties and they therefore are two separate substances. Therefore if someone were to do something to harm the body such as chop off an arm, a leg, or a finger it does not affect the mind in any way, and the mind will still work the same way I would if the body were not harmed.


Descartes argument may be valid and sound but it is false. Cutting off a limb might not effect the mind but if you were cut out certain other pieces of the body then it would have a large profound effect on the mind and change a persons personality. One of these parts is the brain, which if someone’s skull was cut open and pieces were cut from the brain, damaged, or mutilated in any way it would mean that the person would have a completely different personality from the one they were born with and known to have. One real life example of this would be Phineas Gage. Gage was the foremen of a crew cutting a railroad bed in 1848. An accident occurred during the work causing an iron rod to shoot straight through his left frontal lobe and landed several feet away from him. Because of this accident he was blinded in his left and had a complete personality change, he became a completely different person.

Before his accident Gage had a happy-go-lucky personality, loved his friends, was laid back but followed orders and plans, and everyone saw him as a good man. After the accident his friends didn’t see him as Gage any more the way they saw him was that Gage was gone. His personality had gone down the drain, he basically became a douchebag. He was no longer a happy-go-lucky person. He became very rude, started a habit of spewing very gross, vulgar profanities, no longer loved his friends and others the way he used to, and no longer followed orders or the plans laid out for him. Because his left frontal lobe was damaged in the accident Gage became a completely different person, because it effected his personality, which is controlled by the mind, which means that when his body was effected so was his mind. This proves that harming the body and cutting up the body can in ways effect the mind showing and proving Descartes’ argument that the mind and body are separate entities to be a false argument. The accident also caused him to become slightly mentally unstable. Because his metal state was effected it means that his mind had to have been effected which is another way to show Decartes’ argument to be false. His mental state did eventually go back to being stable and steady after working as a coach driver for sometime but his personality never went back to the happy-go- lucky nice guy he was, but stayed the vulgar douchebag he became because of the brain damage also proving that harming the body will and can also harm effect, and change someones state of mind.


In conclusion Descartes argues for dualism by saying that the mind and body are two separate entities which do not share the same properties, the mind being an indivisible mental substance and the body being a divisible physical substances, believing that harming the body in any way will not effect the mind in any way. Phineas Gage, a railroad foreman in 1848, had a iron rod shoot straight through his left frontal lobe and blind him in his left eye, causing his personality to completely change from happy-go-lucky nice guy to rude, vulgar douchebag, showing that harming the body can in many ways effect and harm the mind. The story of Phineas Gage shows that the mind and body may not share the same properties, and may be two different kinds of substances, but they are linked as one united complete entity proving Decartes argument for dualism to be false.

Even if this seems to prove that the mind and body are one entity and harming the body does effect the mind, I will still hold and stay true to my belief that they are two separate entities being that after the body dies the mind which I believe is the soul will live on in Heaven if they believe that God is the one and only true God and serve him and love him or Hell if they do not.