Most people think that consciousness is transparent, that it yields to introspection and that each person has a full and accurate picture of his/her own mind. But consider these lines from a fictional character in Marvin Minsky's Alienable Rights:
"Brains evolved to use parallel distributed processing. In other words, most of their decisions are made by adding up the outputs of thousands of brain cells - and most brain cells are involved in thousands of different types of decisions... the trillions of synapses involved in this make it almost impossible for the other parts of their brain to figure out how those decisions are made. So far as their higher level reasoning can tell, those decisions just happen - without any cause."
"Consciousness means knowing what's been happening in your mind. And although humans claim that they're self-aware, they have scarcely a clue about what their minds do. They don't seem to have the faintest idea of how they construct their new ideas, or choose words and form them into sentences. Instead, they say, 'Something just occurred to me' - as though someone else had done it to them."