The Existence of Existence Among Other Things

"I think, therefor I am." René Descartes stated that he knew that he existed due to the fact that he had thoughts. How then, could he know that the people around him existed? Couldn't it be feasible to argue that if there is no proof that someone else has thoughts (i.e., if you can't experience their thoughts, how do you know those thoughts exist), then how do we know that those around us exist? …

…dreaming. Some people can remember every detail about a dream one night, and then only remember a face in a dream the next. Some nights, one might not remember a single moment of the dream. For years, humans have argued that the possibility of past lives exist. So, if we consider the idea of waking into a new dream world after death, then this is probably where the idea of reincarnation might have originated from.