It is a double pleasure to deceive the deceiver.

Most of the luxuries, and many of the so-called comforts, of life are not only not indispensable, but positive hindrances to the elevation of mankind.

If you hold a cat by the tail you learn things you cannot learn any other way.

In the ordinary business of life, industry can do anything which genius can do, and very many things which it cannot.

Keep your attention focused entirely on what is truly your own concern, and be clear that what belongs to others is their business and none of yours.

Whatever you do in life, surround yourself with smart people who'll argue with you.

Our life does not develop as a result of chance, but as a result of causes.

The world is a comedy to those that think, and a tragedy to those that feel.

The things which . . . are esteemed as the greatest good of all . . . can be reduced to these three headings: to wit, Riches, Fame, and Pleasure. With these three the mind is so engrossed that it cannot scarcely think of any other good.

The real question is not whether life exists after death. The real question is whether you are alive before death.

The hardest thing to explain is the glaring evident which everybody had decided not to see.

Sometimes I wonder whether the world is being run by smart people who are putting us on, or by imbeciles who really man it.