You believe in a god that plays dice; I believe in law & order.

If you're not sure why you're doing something, you can never do enough of it. Imagination is more important than knowledge.

[I] must seek in the stars that which was denied [to me] on earth.

Your fervent wishes can only find fulfillment if you succeed in attaining love and understanding of men, and animals, and plants, and stars, so that every joy becomes your joy and every pain your pain.

Creating a new theory is not like destroying an old barn and erecting a skyscraper in its place. It is rather like climbing a mountain and gaining new and wider views.

I think and think for months and years. Ninety-nine times, the conclusion is false. The hundredth time I am right.

Freedom of teaching and of opinion in book or press is the foundation for the sound and natural development of any people.