Human behavior flows from three main sources: desire, emotion, and knowledge

The ability to observe without evaluating is the highest form of intelligence.

What is freedom of expression? Without the freedom to offend, it ceases to exist.

Books! I dunno if I ever told you this, but books are the greatest gift one person can give another.

I learned very early the difference between knowing the name of something and knowing something.

I decided to teach because I think that any person who studies philosophy has to be involved actively.

Books are for people who wish they were somewhere else.

The great difficulty in education is to get experience out of ideas.

The progressive development of man is vitally dependent on invention.

Any knowledge that doesn't lead to new questions quickly dies out: it fails to maintain the temperature required for sustaining life.

The delight of opening a new pursuit, or a new course of reading, imparts the vivacity and novelty of youth even to old age.

Learning gives creativity, Creativity leads to thinking, Thinking provides knowledge, Knowledge makes you great.

Seek knowledge from the cradle to the grave.

I have no special talents. I am only passionately curious.

The schools ain't what they used to be and never was.

I had rather excel others in the knowledge of what is excellent, than in the extent of my power and dominion

Real knowledge is to know the extent of one's ignorance.

As we acquire more knowledge, things do not become more comprehensible but more mysterious.

A witty saying proves nothing.

Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours.

Industrialize or perish.