To discover a system for the avoidance of war is a vital need of our civilisation.

The axiomatic method has many advantages over honest work.

Change is scientific; progress is ethical; change is indubitable, whereas progress is a matter of controversy.

To the primitive mind, everything is either friendly or hostile; but experience has shown that friendliness and hostility are not the conceptions by which the world is to be understood.

The Mormons had a divine revelation in favour of polygamy, but under pressure from the United States Government they discovered that the revelation was not binding.

When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others.

Bad philosophers may have a certain influence; good philosophers, never.