The importance of a problem should not be judged by the number of pages devoted to it.

Even though the realms of religion and science in themselves are clearly marked off from each other, nevertheless there exist between the two strong reciprocal relationships and dependencies.

But in physics I soon learned to scent out the paths that led to the depths, and to disregard everything else, all the many things that clutter up the mind, and divert it from the essential. The hitch in this was, of course, the fact that one had to cram all this stuff into one's mind for the examination, whether one liked it or not.

Concepts that have proven useful in ordering things easily achieve such authority over us that we forget their earthly origins and accept them as unalterable givens.

Strange is our situation here on earth. Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose.

Then there are the fanatical atheists whose intolerance is of the same kind as the intolerance of the religious fanatics and comes from the same source.

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.