The ultimate test of what a truth means is the conduct it dictates or inspires.

An educated memory depends on an organized system of associations; and its goodness depends on two of their peculiarities: first, on the persistency of the associations; and, second, on their number.

First... a new theory is attacked as absurd; then it is admitted to be true, but obvious and insignificant; finally it is seen to be so important that its adversaries claim that they themselves discovered it.

The desire to gain wealth and the fear to lose it are our chief breeders of cowardice and propagators of corruption.

Ingenuity in meeting and pursuing the pupil, that tact for the concrete situation, though they are the alpha and omega of the teacher's art, are things to which psychology cannot help us in the least.

The first thing that intellect does with an object is to class it with something else.

The perfection of rottenness.