The oldest, shortest words- 'yes' and 'no'- are those which require the most thought.

Common sense is in spite of, not as the result of education.

There are four ways, and only four ways, in which we have contact with the world. We are evaluated and classified by these four contacts: what we do, how we look, what we say, and how we say it.

If you're happy, don't worry you'll get over it.

The greatest minds are capable of the greatest vices as well as of the greatest virtues.

What's done can't be undone.

Experience teaches us that it is much easier to prevent an enemy from posting themselves than it is to dislodge them after they have got possession.

Never put off for tomorrow, what you can do today.

Nothing fixes a thing so intensely in the memory as the wish to forget it.

An understanding of the natural world is a source of not only great curiosity, but great fulfilment.

Peace is not an absence of war, it is a virtue, a state of mind, a disposition for benevolence, confidence, justice.

A house divided against itself cannot stand.

Every intelligent individual wants to know what makes him tick, and yet is at once fascinated and frustrated by the fact that oneself is the most difficult of all things to know.

Man is the only creature who refuses to be what he is.

One of the truest tests of integrity is its blunt refusal to be compromised.

Let no man pull you low enough to hate him.

To be one, to be united is a great thing. But to respect the right to be different is maybe even greater.

He who conquers others is strong; he who conquers himself is mighty.

He that cannot reason is a fool. He that will not is a bigot. He that dare not is a slave.

Boredom is the root of all evil - the despairing refusal to be oneself.

Taste every fruit of every tree in the garden at least once. It is an insult to creation not to experience it fully. Temperance is wickedness.