The satisfaction to be derived from success in a great constructive enterprise is one of the most massive that life has to offer.

The desire to understand the world and the desire to reform it are the two great engines of progress, without which human society would stand still or retrogress.

Physics, owing to the simplicity of its subject matter, has reached a higher state of development than any other science.

Marriage is for women the commonest mode of livelihood, and the total amount of undesired sex endured by women is probably greater in marriage than in prostitution.

Men have physical needs, and they have emotions. While physical needs are unsatisfied, they take first place; but when they are satisfied, emotions unconnected with them become important in deciding whether a man is to be happy or unhappy.

The people who are regarded as moral luminaries are those who forego ordinary pleasures themselves and find compensation in interfering with the pleasures of others.

no one ever gossips about the virtues of others