" There are many levels in the human mental structure-certainly it is a system which we do not understand very well yet. But there are hundreds of rival theories which tell why people act the way they do, each theory based on some underlying assumptions about how far down in this set of levels various kinds of psychological "forces" are found. Since at this time we use pretty much the same kind of language for all mental levels, this makes for much level-mixing and most certainly for hundreds of wrong theories. For instance, we talk of "drives"-for sex, for power, for fame, for love, etc., etc.-without knowing where these drives come from in the human mental structure. Without belaboring the point, I simply wish to say that our confusion about who we are is certainly related to the fact that we consist of a large set of levels, and we use overlapping language to describe ourselves on all of those levels. "
― Douglas R. Hofstadter , Gödel, Escher, Bach: An Eternal Golden Braid