Students and scholars of all kinds and of every age aim, as a rule, only at information, not insight. They make it a point of honour to have information about everything, every stone, plant, battle, or experiment and about all books, collectively and individually. It never occurs to them that information is merely a means to insight, but in itself is of little or no value.

Everybody's friend is nobody's.

Consider the Koran... this wretched book was sufficient to start a world-religion, to satisfy the metaphysical need of countless millions for twelve hundred years, to become the basis of their morality and of a remarkable contempt for death, and also to inspire them to bloody wars and the most extensive conquests. In this book we find the saddest and poorest form of theism. Much may be lost in translation, but I have not been able to discover in it one single idea of value.

Philosophy ... is a science, and as such has no articles of faith; accordingly, in it nothing can be assumed as existing except what is either positively given empirically, or demonstrated through indubitable conclusions.

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.

Pride is generally censured and decried, but mainly by those who have nothing to be proud of.

Reading is merely a surrogate for thinking for yourself; it means letting someone else direct your thoughts.