Moderation in temper is always a virtue; but moderation in principle is always a vice.

No act of kindness, no matter how small, is ever wasted.

Science may set limits to knowledge, but should not set limits to imagination.

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

If you have no problems, then you have no clue to what is going.

Immoderate desire is the mark of a child, not a man.

You cannot truly listen to anyone and do anything else at the same time.

It is hard to fight desire; but to control it is the sign of a reasonable man.

It is not enough to have a good mind; the main thing is to use it well.

It takes a great deal of bravery to stand up to our enemies, but just as much to stand up to our friends.

Let there be spaces in your togetherness.

Medicine heals diseases of the body, wisdom frees the soul from passions.

Do not pray for an easy life, pray for the strength to endure a difficult one.

If we do not lay out ourselves in the service of mankind whom should we serve?

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

Although our intellect always longs for clarity and certainty, our nature often finds uncertainty fascinating.

Men are not prisoners of fate, but only prisoners of their own minds.

Nature is pleased with simplicity. And nature is no dummy

Happiness is not an ideal of reason, but of imagination.

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

Adapt what is useful, reject what is useless, and add what is specifically your own.