Every one of us has a sense of the world, and we all know that this sense is in part given to us by what other people and society tell us; in part generated by our emotional state, which we project outward; and in part by our genuine perceptions of reality. In short, our struggle to determine what is true is the struggle to decide which of our perceptions is genuine, and which are false because they are handed down, or sold to us, or generated by our own hopes and fears.