"Human knowledge is dark and uncertain; philosophy is dark, astrology is dark, and geometry is dark"

"The philosophy of one century is the common sense of the next"

"Education is a private matter between the person and the world of knowledge and experience, and has little to do with school or college"

"What we want is to see the child in pursuit of knowledge, and not knowledge in pursuit of the child"

"A good decision is based on knowledge and not on numbers"

"A lawyer without history or literature is a mechanic, a mere working mason; if he possesses some knowledge of these, he may venture to call himself an architect"

"I am now convinced that theoretical physics is actually philosophy"

"The philosophy of the school room in one generation will be the philosophy of government in the next"

"Knowledge of what is possible is the beginning of happiness"

"Perplexity is the beginning of knowledge"

"The seat of knowledge is in the head, of wisdom, in the heart"