Leonardo da Vinci

The eye, which is called the window of the soul, is the chief means whereby the understanding may most fully and abundantly appreciate the infinite works of nature.

Nothing can be loved or hated unless it is first understood.

The poet ranks far below the painter in the representation of visible things, and far below the musician in that of invisible things.

In rivers, the water that you touch is the last of what has passed and the first of that which comes; so with present time.

The depth and strength of a human character are defined by its moral reserves.

Just as food eaten without appetite is a tedious nourishment, so does study without zeal damage the memory by not assimilating what it absorbs.

To lie is so vile, that even if it were in speaking well of godly things it would take off something from God’s grace; and Truth is so excellent, that if it praises but small things they become noble.

The acquisition of any knowledge is always of use to the intellect, because it may thus drive out useless things and retain the good.

The painter who draws merely by practice and by eye, without any reason, is like a mirror which copies every thing placed in front of it without being conscious of their existence.

Man is the model of the world.

Our life is made by the death of others.

The air is full of endless lines, straight and radiating, intercrossing and interweaving, without ever coinciding one with another; and they represent for every object the true form of their reason (or their explanation).

Human subtlety will never devise an invention more beautiful, more simple or more direct than does nature because in her inventions nothing is lacking, and nothing is superfluous.

Necessity is the mistress and guide of nature. Necessity is the theme and inventress of nature, the curb and law and theme.

For once you have tasted flight you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return.

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

The promise given was a necessity of the past: the word broken is a necessity of the present.

There is no result in nature without a cause; understand the cause and you will have no need of the experiment.