Summary of Descartes Meditation III and IV .
Meditation III was quite difficult to decipher, but I was able to understand that Descartes was using his methods of doubt and analysis. He talks about certainty, earth, the sky, and his senses. His meditation contains a very difficult proof of God's existence. He claims that things, which are "clearly and distinctly perceived", are completely true. .
Descartes also discusses the truths of mathematics (2+3=5). He could not bring himself to doubt mathematics, any more than he can his own existence. Yet, there is still doubt. However, he wants to prove that God exists and is not a deceiver. If God exists than an all-powerful evil genius is not possible. .
Descartes certainties include him, this thought process, and that the essence of matter is flexible, changeable, and extended. He classifies his ideas and thoughts in order to determine which of them are truthful and untruthful. There are images of things, speaking ideas, volitions, emotions, and judgments. .
He than classified his ideas by their origin. He said that some ideas appear to be natural, some caused by things outside of him, and some invented by him. Descartes has two reasons for thinking that ideas resemble things. One is that nature seems to have taught him this. Secondly, many ideas appear in his mind independent of his will which implies that they do not depend simply upon him. He feels the heat from the fire whether he wants to or not. .
Descartes than talks about "objective", "formal", and "eminent" reality. He also talks about "substance," which means that a thing which exists independently. Basically, if my pen broke, my computer will still exist despite the broken pen. Therefore, modes and accidents are dependent of substances for their existence.
