Leonardo da Vinci

Not to punish evil is equivalent to authorizing it.

If the painter has clumsy hands, he will be apt to introduce them into his works, and so of any other part of his person, which may not happen to be so beautiful as it ought to be. He must, therefore, guard particularly against that self-love, or too good opinion of his own person, and study by every means to acquire the knowledge of what is most beautiful, and of his own defects, that he may adopt the one and avoid the other.

Fine gold is recognized when it is tested.

No counsel is more sincere than that given on ships which are in danger.

The eye which turns from a white object in the light of the sun and goes into a less fully lighted place will see everything as dark.

Learning never exhausts the mind.

Wisdom is the daughter of experience

Realize that everything connects to everything else.

As a well spent day brings happy sleep, so life well used brings happy death.

I am fully conscious that, not being a literary man , certain presumptuous persons will think that they may reasonably blame me; alleging that I am not a man of letters. Foolish folks! do they not know that I might retort as Marius did to the Roman Patricians by saying: That they, who deck themselves out in the labours of others will not allow me my own. They will say that I, having no literary skill, cannot properly express that which I desire to treat of, but they do not know that my subjects are to be dealt with by experience rather than by words; and experience has been the mistress of those who wrote well. And so, as mistress, I will cite her in all cases.

If you are alone you belong entirely to yourself. If you are accompanied by even one companion you belong only half to yourself or even less in proportion to the thoughtlessness of his conduct and if you have more than one companion you will fall more deeply into the same plight.

It is an acknowledged fact that we perceive errors in the work of others more readily than in our own.

The function of muscle is to pull and not to push, except in the case of the genitals and the tongue.

As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.

Truth at last cannot be hidden. Dissimulation is of no avail. Dissimulation is to no purpose before so great a judge. Falsehood puts on a mask. Nothing is hidden under the sun.

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.

Water is the driving force in nature.

Just as a well-filled day brings blessed sleep, so a well-employed life brings a blessed death