Nothing is more sad than the death of an illusion.

The progress of science is strewn, like an ancient desert trail, with the bleached skeleton of discarded theories which once seemed to possess eternal life.

The most persistent sound which reverberates through man's history is the beating of war drums.

Creative activity could be described as a type of learning process where teacher and pupil are located in the same individual.

Politics can be relatively fair in the breathing spaces of history; at its critical turning points there is no other rule possible than the old one, that the end justifies the means.

Courage is never to let your actions be influenced by your fears.