Thought is great and swift and free, the light of the world, the chief glory of man.

Suppose atomic bombs had reduced the population of the world to one brother and sister; should they let the human race die out?

The scientific attitude of mind involves a sweeping away of all other desires in the interest of the desire to know.

Our individual life is brief, and perhaps the whole life of mankind will be brief if measured in astronomical scale

Moral progress has consisted in the main of protest against cruel customs, and of attempts to enlarge human sympathy.

Mankind has become so much one family that we cannot insure our own prosperity except by insuring that of everyone else.

There can't be a practical reason for believing something that is not true.