For 13 to be unlucky would require there to be some kind of cosmic intelligence that counts things that humans count and that also makes certain things happen on certain dates or in certain places according to whether the number 13 'is involved' or not (whatever 'is involved' might mean).

Son, always tell the truth. Then you'll never have to remember what you said the last time.

Sam Rayburn

Learning without thought is labor lost. Thought without learning is perilous.

Confucius

You cannot teach a man anything; you can only help him find it within himself.

Galileo Galilei

I know now that there is no one thing that is true -- it is all true.

Ernest Hemingway

If men knew how women pass the time when they are alone, they'd never marry.

O. Henry

In this world it is not what we take up, but what we give up, that makes us rich.

Henry Ward Beecher

In business or in life, don't follow the wagon tracks too closely.

H. Jackson Brown, Jr.

Books are my friends, my companions. They make me laugh and cry and find meaning in life.

Christopher Paolini

People that are orthodox when they are young are in danger of being middle-aged all their lives.

Walter Lippmann

Only that which makes you feel bad after doing is immoral.

Ernest Hemingway

Fine art, that exists for itself alone, is art in a final state of impotence. If nobody, including the artist, acknowledges art as a means of knowing the world, then art is relegated to a kind of rumpus room of the mind and the irresponsibility of the artist and the irrelevance of art to actual living becomes part and parcel of the practice of art.

Angela Carter

The professors must not prevent us from realizing that history is fun, and that the most bizarre things really happen

Bertrand Russell