Life isn't worth living, unless it is lived for someone else.

Galileo had already made a significant beginning toward a knowledge of the law of motion. He discovered the law of inertia and the law of bodies falling freely in the gravitational field of the earth.

I do not believe in immortality of the individual, and I consider ethics to be an exclusively human concern with no superhuman authority behind it.

You have to color outside the lines once in a while if you want to make your life a masterpiece.

Empathy is patiently and sincerely seeing the world through the other person's eyes. It is not learned in school; it is cultivated over a lifetime.

The only thing that you absolutely have to know, is the location of the library.

We can invent as many theories we like, and any one of them can be made to fit the facts. But that theory is always preferred which makes the fewest number of assumptions.