No system has ever as yet existed which did not in some form involve the exploitation of some human beings for the advantage of others.

Even dogs and horses have their actions modified by association with human beings; they form different habits because human beings are concerned with what they do.

Thought is impossible without words.

Failure is instructive. The person who really thinks learns quite as much from his failures as from his successes. Genuine ignorance is profitable because it is likely to be accompanied by humility, curiosity, and open-mindedness; whereas ability to repeat catch-phrases, can't terms, familiar propositions, gives the conceit of learning and coats the mind with varnish waterproof to new ideas.

Instruction is important.

The primary ineluctable facts of the birth and death of each one of the constituent members in a social group determine the necessity of education.

To avoid a split between what men consciously know because they are aware of having learned it by a specific job of learning, and what they unconsciously know because they have absorbed it in the formation of their characters by intercourse with others, becomes an increasingly delicate task with every development of special schooling.