Why did it occur to anyone to believe in only one God? And conversely why did it ever occur to anyone to believe in many gods? To both these questions we must return the same answer: Because that is how the human mind happens to work. For the human mind is both diverse and simple, simultaneously many and one. We have an immediate perception of our own diversity and of that of the outside world. And at the same time we have immediate perceptions of our own oneness.