Stapledon's philosophy background probably helped, among other things. Word is that Arthur C. Clarke was directly influenced by reading his stuff too.

I honestly found Odd John rather tiresome at times (too pseudo-Nietzche plus tired early-twentieth-century myth of progress, the combination seems to rub me the wrong way), though it's got some great... Stapledonisms (?) sprinkled around. I also liked Sirius. The books Last Men in London and Death into Life are on my reading list with a pile of other things.