Every kind of peaceful cooperation among men is primarily based on mutual trust and only secondarily on institutions such as courts of justice and police.

If I were not a Jew I would be a Quaker.

Science without religion is lame, religion without science is blind.

... it is a welcome symptom in an age which is commonly denounced as materialistic, that it makes heroes of men whose goals lie wholly in the intellectual and moral sphere.

We can invent as many theories we like, and any one of them can be made to fit the facts. But that theory is always preferred which makes the fewest number of assumptions.

All that is valuable in human society depends upon the opportunity for development accorded the individual.

The thinking that got us to where we are is not the thinking that will get us to where we want to be.