There are three ways of securing a society that shall be stable as regards population. The first is that of birth control, the second that of infanticide or really destructive wars, and the third that of general misery except for a powerful minority.

(on A History of Western Philosophy) I was sometimes accused by reviewers of writing not a true history but a biased account of the events that I arbitrarily chose to write of. But to my mind, a man without a bias cannot write interesting history - if, indeed, such man exists.

Right discipline consists, not in external compulsion, but in the habits of mind which lead spontaneously to desirable rather than undesirable activities.

A smile happens in a flash, but its memory can last a lifetime.

The fundamental defect of fathers, in our competitive society, is that they want their children to be a credit to them. We all feel instinctively, that our children's success reflect glory upon ourselves, while their failures make us feel shame. Unfortunately, the successes which cause us to swell with pride are often of an undesirable kind.... Neither happiness nor virtue, but worldly success, is what the average father desires for his children.

It appeared that after first contemplating a book on some subject, and after giving serious preliminary attention to it, I needed a period of subconscious incubation which could not be hurried and was if anything impeded by deliberate thinking.... Having, by a time of very intense concentration, planted the problem in my subconsciousness, it would germinate underground until, suddenly, the solution emerged with a blinding clarity, so that it only remained to write down what happened as if in a revelation.

Whether science-and indeed civilization in general-can long survive depends upon psychology, that is to say, it depends upon what human beings desire.