I thought most of what PKD wrote was mindfucks, but they are nothing compared to this. If you are interested in checking him out, do not start with this one, its very, very different from the rest of his body of work.

What was hard to handle was it was written in an autobiographical way about someone grappling with whether there is a higher power or not. And that someone has split personalities which are both entirely rational and completely insane at the same time. So you're getting both sides in an extremely well told narrative, which makes you start to feel a little insane yourself.

One word summary: Fascinating