Philosophical or Psychology books for an agnostic (NOT Atheist)?

Tertium Organum, A New Model of the Universe, The Fourth Way, and In Search of the Miraculous, by P.D. Ouspensy. written from 1909-1945. I think you might like these. Ospensky was a student of Georges Gurdjeff, a nineteenth century magician and mystic. He has a way of explaining the enigmas of the world, particularly the problems of space-time, new dimensions, and mysticism in a cut-and-dried comprehensible way, years before Einstein. You can find them in used book stores I know, but were still in print last I checked.