Argument b/w what is conceivable and what is possible: therefore, my mind is not the same as my body, they are numerically identical (necessary truth) Its not saying that the body is not causally interacting with the mind; they are both different things: descartes clean and distinct ideas, conceive means imagine for this lecture, something be can conceivable yet impossible. 3 follows from 2 but 2 doesn"t necessarily follow from 1: ex. Mythical creatures can survive even if heart ripped out of them it possible to imagine this but yet seems impossible that hey still lived. Objections: conceivability doesn"t strictly imply possibility need this to be true to go from 1 to 2, nonlogical possibility- possibility given the laws of nature, ex. If you walk off a cliff, you will fall: logical possibility- possibility given that there is no logical contradiction, ex.