In proportion to the development of his individuality, each person becomes more valuable to himself, and is therefore capable of being more valuable to others. . . .

In this age, the mere example of nonconformity, the mere refusal to bend the knee to custom, is itself a service.

Genius can only breathe freely in an atmosphere of freedom.

Protection, therefore, against the tyranny of the magistrate is not enough; there needs protection against the tyranny of the prevailing opinion and feeling, against the tendency of society to impose, by other means than civil penalties, its own ideas and practices as rules of conduct on those who dissent from them.

All social inequalities which have ceased to be considered expedient, assume the character not of simple inexpediency, but of injustice, and appear so tyrannical, that people are apt to wonder how they ever could have. been tolerated; forgetful that they themselves perhaps tolerate other inequalities under an equally mistaken notion of expediency, the correction of which would make that which they approve seem quite as monstrous as what they have at last learnt to condemn.

The application of algebra to geometry ... has immortalized the name of Descartes, and constitutes the greatest single step ever made in the progress of the exact sciences.

It is given to no human being to stereotype a set of truths, and walk safely by their guidance with his mind's eye closed.