I conclude that, while it is true that science cannot decide questions of value, that is because they cannot be intellectually decided at all, and lie outside the realm of truth and falsehood. Whatever knowledge is attainable, must be attained by scientific methods; and what science cannot discover, mankind cannot know.

In democratic countries, the most important private organizations are economic. Unlike secret societies, they are able to exercise their terrorism without illegality, since they do not threaten to kill their enemies, but only to starve them.

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

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

Patriotism is the willingness to kill and be killed for trivial reasons.

Man is the product of causes which had no prevision of the end they were achieving; his origin, his growth, his hopes and fears, his loves and beliefs, are but the outcome of accidental collocations of atoms; no fire, no heroism, no intensity of though and feeling, can preserve an individual life beyond the grave.

In science the successors stand upon the shoulders of their predecessors; where one man of supreme genius has invented a method, a thousand lesser men can apply it. ... In art nothing worth doing can be done without genius; in science even a very moderate capacity can contribute to a supreme achievement.