We know very little, and yet it is astonishing that we know so much, and still more astonishing that so little knowledge can give us so much power.

In attempting to understand the elements out of which mental phenomena are compounded, it is of the greatest importance to remember that from the protozoa to man there is nowhere a very wide gap either in structure or in behaviour. From this fact it is a highly probable inference that there is also nowhere a very wide mental gap.

True happiness for human beings is possible only to those who develop their godlike potentialities to the utmost.

Descartes, the father of modern philosophy ... would never-so he assures us-have been led to construct his philosophy if he had had only one teacher, for then he would have believed what he had been told; but, finding that his professors disagreed with each other, he was forced to conclude that no existing doctrine was certain.

A million million years gives us some time to prepare for the end . . . let us make the best of it.

Men who are unhappy, like men who sleep badly, are always proud of the fact.

You must believe that you can help bring about a better world. A good society is produced only by good individuals, just as truly as a majority in a presidential election is produced by the votes of single electors.