The mind can proceed only so far upon what it knows and can prove. There comes a point where the mind takes a higher plane of knowledge, but can never prove how it got there. All great discoveries have involved such a leap

As far as I'm concerned, I prefer silent vice to ostentatious virtue.

The best design is the simplest one that works.

Consider the concepts referred to in the words 'where', 'when', 'why', 'being', to the elucidation of which innumerable volumes of philosophy have been devoted. We fare no better in our speculations than a fish which should strive to become clear as to what is water.

We still do not know one thousandth of one percent of what nature has revealed to us.

In my personal experience I have hardly come to know the wretchedness of mankind better than as a result of the general theory of relativity and everything connected to it. But it doesn't bother me.

No path leads from a knowledge of that which is to that which should be.