The importance of an individual thinker owes something to chance. For it depends upon the fate of his ideas in the minds of his successors.

Dogmatism is the anti-Christ of learning.

There is no nature at an instant.

War can protect; it cannot create.

No man of science wants merely to know. He acquires knowledge to appease his passion for discovery. He does not discover in order to know, he knows in order to discover.

It is not paradox to say that in our most theoretical moods we may be nearest to our most practical applications.

Inventive genius requires pleasurable mental activity as a condition for its vigorous exercise. "Necessity is the mother of invention" is a silly proverb. "Necessity is the mother of futile dodges" is much closer to the truth. The basis of growth of modern invention is science, and science is almost wholly the outgrowth of pleasurable intellectual curiosity.