The faculty for remembering is not diminished in proportion to what one has learnt, just as little as the number of moulds in which you cast sand lessens its capacity for being cast in new moulds.

A man's knowledge may be said to be mature, in other words, when it has reached the most complete state of perfection to which he, as an individual, is capable of bringing it, when an exact correspondence is established between the whole of his abstract ideas and the things he has actually perceived for himself. His will mean that each of his abstract ideas rests, directly or indirectly, upon a basis of observation, which alone endows it with any real value; and also that he is able to place every observation he makes under the right abstract idea which belongs to it.

A man may call to mind the face of his friend, but not his own. Here, then, is an initial difficulty in the way of applying the maxim, Know Thyself.

Reading is a mere makeshift for original thinking.

With people of limited ability modesty is merely honesty. But with those who possess great talent it is hypocrisy.

We will gradually become indifferent to what goes on in the minds of other people when we acquire a knowledge of the superficial nature of their thoughts, the narrowness of their views and of the number of their errors. Whoever attaches a lot of value to the opinions of others pays them too much honor.

In early youth, as we contemplate our coming life, we are like children in a theatre before the curtain is raised, sitting there in high spirits and eagerly waiting for the play to begin.