Leonardo da Vinci

The act of procreation and anything that has any relation to it is so disgusting that human beings would soon die out if there were no pretty faces and sensuous dispositions.

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.

One can have no greater or lesser mastery than of oneself.

Animals will be seen on the earth who will always be fighting against each other with the greatest loss and frequent deaths on each side. And there will be no end to their malignity; by their strong limbs we shall see a great portion of the trees of the vast forests laid low throughout the universe; and, when they are filled with food the satisfaction of their desires will be to deal death and grief and labour and wars and fury to every living thing; and from their immoderate pride they will desire to rise towards heaven, but the too great weight of their limbs will keep them down. Nothing will remain on earth, or under the earth or in the waters which will not be persecuted, disturbed and spoiled, and those of one country removed into another. And their bodies will become the sepulture and means of transit of all they have killed. O Earth! why dost thou not open and engulf them in the fissures of thy vast abyss and caverns, and no longer display in the sight of heaven such a cruel and horrible monster?

He who does not punish evil commands it to be done.

We do not lack devices for measuring these miserable days of ours, in which it should be our pleasure that they be not frittered away without leaving behind any memory of ourselves in the mind of men.

I expose to men the origin of their first, and perhaps second, reason for existing.

Where the spirit does not work with the hand, there is no art. Nature is the source of all true knowledge. She has her own logic, her own laws, she has no effect without cause nor invention without necessity.

Learning is the only thing the mind never exhausts, never fears and never regrets.

It's not enough that you believe what you see. You must also understand what you see.

Everything in some way connects to everything else.

Obstacles cannot crush me...he who is fixed to a star does not change his mind.

Painting is poetry which is seen and not heard, and poetry is a painting which is heard but not seen.

Fine gold is recognized when it is tested.

There is nothing which deceives us as much as our own judgement.

I believe man will fly and I base this assumption on the fact that God has blessed us with minds that are capable of imagining it. Anything that can be dreamt of will eventually be built. Anyone who says otherwise is a fool.

A beautiful body perishes, but a work of art dies not.

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.

That which can be lost cannot be deemed riches. Virtue is our true wealth and the true reward of its possessor; it cannot be lost, it never deserts us until life leaves us. Hold property and external riches with fear; they often leave their possessor scorned and mocked at for having lost them.

Most people, if you give them a book, they sniff around on it awhile, then try to eat it.

The abbreviators of works do injury to knowledge and to love.Of what value is he who,in order to abbreviate the parts of those things of which he professes to give complete knowledge,leaves out the greater part of the things of which the whole is composed?Oh human stupidity!You don’t see that you are falling into the same error as one who strips a tree of its adornment of branches full of leaves,intermingled with fragrant flowers or fruit in order to demonstrate that the tree is good for making planks.

Tell me if anything was ever done... Tell me... Tell me.

As iron rusts when not used, and water gets foul from standing or turns to ice when exposed to cold, so the intellect degenerates without exercise.

He who does not value life does not deserve it.

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.

No human investigation can be called real knowledge if it does not pass through mathematical demonstrations; and if you say that the kinds of knowledge that begin and end in the mind have any value as truth, this cannot be conceded, but rather must be denied for many reasons, and first of all because in such mental discussions there is no experimentation, without which nothing provides certainty of itself.

Instrumental or mechanical science is the noblest and, above all others, the most useful.

The air moves like a river and carries the clouds with it; just as running water carries all the things that float upon it.

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

My body is not a tomb for other creatures.