The greatest geniuses sometimes accomplish more when they work less.

life without love, is no life at all

Being willing is not enough. We must do.

Mechanics is the paradise of the mathematical sciences because by means of it one comes to the fruits of mathematics.

The color of the object illuminated partakes of the color of that which illuminates it.

The earth is moved from its position by the weight of a tiny bird resting upon it.

It should not be hard for you to stop sometimes and look into the stains of walls, or ashes of a fire, or clouds, or mud or like places, in which...you may find really marvellous ideas.