A proverb is one man's wit and all men's wisdom.

All knowledge, we feel, must be built up upon our instinctive beliefs; and if these are rejected, nothing is left.

I did not know I loved you until I heard myself telling so, for one instance I thought, "Good God, what have I said?" and then I knew it was true.

Understanding human nature must be the basis of any real improvement in human life. Science has done wonders in mastering the laws of the physical world, but our own nature is much less understood, as yet, than the nature of stars and electrons. When science learns to understand human nature, it will be able to bring a happiness into our lives which machines and the physical sciences have failed to create.

Arithmetic must be discovered in just the same sense in which Columbus discovered the West Indies, and we no more create numbers than he created the Indians.

In spreading his ideas, Plato was willing to employ emotional appeals, state propaganda, and the use of force.

Can a society in which thought and technique are scientific persist for a long period, as, for example, ancient Egypt persisted, or does it necessarily contain within itself forces which must bring either decay or explosion?