Of all the intellectual faculties, judgment is the last to mature. A child under the age of fifteen should confine its attention either to subjects like mathematics, in which errors of judgment are impossible, or to subjects in which they are not very dangerous, like languages, natural science, history, etc.

Opinion is like a pendulum and obeys the same law.

universal compassion is the only guarantee of morality.

Life without pain has no meaning.

If two men who were friends in their youth meet again when they are old, after being separated for a life-time, the chief feeling they will have at the sight of each other will be one of complete disappointment at life as a whole; because their thoughts will be carried back to that earlier time when life seemed so fair as it lay spread out before them in the rosy light of dawn, promised so much — and then performed so little.

Money alone is absolutely good, because it is not only a concrete satisfaction of one need in particular; it is an abstract satisfaction of all.

The intellectual attainments of a man who thinks for himself resemble a fine painting, where the light and shade are correct, the tone sustained, the colour perfectly hamonized; it is true to life.