The student of arithmetic who has mastered the first four rules of his art, and successfully striven with money sums and fractions, finds himself confronted by an unbroken expanse of questions known as problems.

I am a great believer in luck, and I find the harder I work the more I have of it.

Writing is no trouble: you just jot down ideas as they occur to you. The jotting is simplicity itself - it is the occurring which is difficult.

The classics are only primitive literature. They belong to the same class as primitive machinery and primitive music and primitive medicine.

A half truth, like half a brick, is always more forcible as an argument than a whole one. It carries better.

It's a lie, but Heaven will forgive you for it.

I detest life-insurance agents: they always argue that I shall some day die, which is not so.