Every man has a right to be wrong in his opinions. But no man has a right to be wrong in his facts.

Don't try to buy at the bottom and sell at the top. It can't be done except by liars.

Millions saw the apple fall, but Newton was the one who asked why.

Old books that have ceased to be of service should no more be abandoned than should old friends who have ceased to give pleasure.

Two things are bad for the heart - running up stairs and running down people.

To me, old age is always 15 years older than I am.

I'm not smart, but I like to observe. Millions saw the apple fall, but Newton was the one who asked why.

Desire is the essence of a man.

The ability to express an idea is well nigh as important as the idea itself.

Will and intellect are one and the same.

Approach each new problem not with a view of finding what you hope will be there, but to get the truth, the realities that must be grappled with. You may not like what you find. In that case you are entitled to try to change it. But do not deceive yourself as to what you do find to be the facts of the situation.

Fame has also this great drawback, that if we pursue it, we must direct our lives so as to please the fancy of men.

If you have made a mistake, cut your losses as quickly as possible.

Never answer a critic, unless he's right.

Only as you do know yourself can your brain serve you as a sharp and efficient tool. Know your own failings, passions, and prejudices so you can separate them from what you see.

Old age is always fifteen years older than I am.