PHIL 100 Lecture Notes - Lecture 20: Cogito Ergo Sum, A Priori And A Posteriori, Evil Demon

• School: University of Maryland
• Department: Philosophy
• Course: PHIL 100
• Professor: Brock Rough

Document Summary

Goal of meditation i: rid myself of even possibly false beliefs. Skeptical methods: illusions allows him to doubt some things but not enough. Not even all sense data: dreams shows that a priori knowledge is more certain than a posteriori knowledge, evil demon even a priori knowledge can be doubted. Goal of meditation ii: discover what can"t be doubted even if there is an evil demon controlling my thoughts. List of things to doubt: anything perceivable by the senses, one"s own body, extension, movement, place. There must be a me that is being deceived. If i think anything, then i necessarily must exist. Cogito ergo sum: i think, therefore i am. What am i: a thing that thinks. Before meditating: the body is well known. Now (after meditating: can imagine myself without a body, cant imagine myself without thinking. Descartes is not offering a proof that other things do not exist.