As the biggest library if it is in disorder is not as useful as a small but well-arranged one, so you may accumulate a vast amount of knowledge but it will be of far less value to you than a much smaller amount if you have not thought it over for yourself; because only through ordering what you know by comparing every truth with every other truth can you take complete possession of your knowledge and get it into your power. You can think about only what you know, so you ought to learn something; on the other hand, you can know only what you have thought about.

To become indignant at [people's] conduct is as foolish as to be angry with a stone because it rolls into your path. And with many people the wisest thing you can do, is to resolve to make use of those whom you cannot alter.

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.

A man can be himself only so long as he is alone; and if he does not love solitude, he will not love freedom; for it is only when he is alone that he is really free.

The nobler and more perfect a thing is, the later and slower it is in arriving at maturity. A man reaches the maturity of his reasoning powers and mental faculties hardly before the age of twenty-eight; a woman at eighteen.

Education perverts the mind since we are directly opposing the natural development of our mind by obtaining ideas first and observations last. This is why so few men of learning have such sound common sense as is quite common among the illiterate.

Intellect is invisible to the man who has none.