It isn't what we don't know that gives us trouble, it's what we know that ain't so.

Evil being the root of mystery, pain is the root of knowledge.

That men do not learn very much from the lessons of history is the most important of all the lessons that history has to teach.

Just because I don't care doesn't mean I don't understand.

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

Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it.

If the facts don't fit the theory, change the facts.

The man who is fond of books is usually a man of lofty thought, and elevated opinions.

I don't look on poetry as closed works. I feel they're going on all the time in my head and I occasionally snip off a length.

Knowledge, Action, Devotion are complementary to each other.

The books that the world calls immoral are books that show the world its own shame.

There is no authority who decides what is a good idea.

The real solution lies in a world in which charity will have become unnecessary.

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

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

My alma mater was books, a good library.... I could spend the rest of my life reading, just satisfying my curiosity.

A thought is an idea in transit.

The knowledge of all things is possible

The first idea the child must acquire is that of the difference between good and evil.

All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind.

Integrity without knowledge is weak and useless, and knowledge without integrity is dangerous and dreadful.