Descartes says the mind is distinct from the body, or anything physical for that matter. He says, a thinking substance is nonphysical or spiritual in nature (mind), and an extended substance is physical, but not capable of consciousness or thought (body). However, this very claim is also his biggest problem as his mind body interaction has many critics and to some, can seem invalid. This is mainly due to the challenge by those who ask how mind and body can interact if they are two different substances altogether. Over Descartes' period of teaching, he has conceived many arguments to support his view of the distinction of mind from body. Again, this was not done without its' skeptics.
To examine Descartes' arguments thoroughly, it is important to begin with "The Cogito". This is that he is sure he exists. However, he raises the possibility of someone only making him think he exists.
"Let him deceive me as much as he can, he will never bring it about that I am nothing so long as I think that I am something."
"I think I Exist". The cogito is what Descartes' was absolutely certain of. He can't be sure of anything except for the fact that he can think if he can think, he must exist as a thinking being. Descartes' regards "The cogito" to have the mark of knowledge present in its theory - clarity and distinctness of perception.
One of his arguments for the real distinction of mind from body also held clear and distinct perception. This is the Argument of Doubt. While Descartes is unsure of the true existence of his body, he cannot doubt that his mind does indeed exist as he is a thinking thing doubting his very own existence. Therefore, through this certainty, Descartes says that he, an existing substance is not the same as his body as it does not exist. However, this is clearly not a valid argument as it does not