We know that there is no absolute knowledge, that there are only theories; but we forget this. The better educated we are, the harder we believe in axioms.

My father, the practical joker, did not care for practical jokes on himself; he did not encourage the practice in me.

My father was slower, but he was severer than my mother, who was quick but light and irregular in discipline.

I never heard a Christian sermon preached in a church.

The commercial spirit is the spirit of profit, not patriotism; of credit, not honor; of individual gain, not national prosperity; of trade and dickering, not principle.

If my father could watch my son for a while, he might realize his own immortality.

I have seen the future, and it works.