I have offended God and mankind because my work didn't reach the quality it should have.

Why does the eye see a thing more clearly in dreams than the imagination when awake?

Marriage is like putting your hand into a bag of snakes in the hope of pulling out an eel.

Our life is made by the death of others.

Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason.

Experience never errs; it is only your judgments that err by promising themselves effects such as are not caused by your experiments.

Marriage is like putting your hand into a bag of snakes in the hope of pulling out an eel.

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

In order to arrive at knowledge of the motions of birds in the air, it is first necessary to acquire knowledge of the winds, which we will prove by the motions of water in itself, and this knowledge will be a step enabling us to arrive at the knowledge of beings that fly between the air and the wind.

For, verily, great love springs from great knowledge of the beloved object, and if you little know it, you will be able to love it only little or not at all.

Intellectual passion drives out sensuality.

He who is fixed to a star does not change his mind.

Good men by nature, wish to know. I know that many will call this useless work... men who desire nothing but material riches and are absolutely devoid of that of wisdom, which is the food and only true riches of the mind.

Just as courage is the danger of life, so is fear its safeguard.

Time stays long enough for anyone who will use it.

Poor is the pupil who does not surpass his master.

Who sows virtue reaps honor.

The noblest pleasure is the joy of understanding.

All our knowledge has its origins in our perceptions.

Where there is shouting, there is no true knowledge.

I love those who can smile in trouble, who can gather strength from distress, and grow brave by reflection. 'Tis the business of little minds to shrink, but they whose heart is firm, and whose conscience approves their conduct, will pursue their principles unto death.

The smallest feline is a masterpiece.

All knowledge which ends in words will die as quickly as it came to life, with the exception of the written word: which is its mechanical part.

The natural desire of good men is knowledge.

Art is never finished, only abandoned.

Men of lofty genius sometimes accomplish the most when they work least, for their minds are occupied with their ideas and the perfection of their conceptions, to which they afterwards give form.

Men of lofty genius when they are doing the least work are most active.

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.

Beyond a doubt truth bears the same relation to falsehood as light to darkness.

The human foot is a masterpiece of engineering and a work of art.

There are three classes of people: those who see, those who see when they are shown, those who do not see.

Learning never exhausts the mind.

Nothing strengthens authority so much as silence.

It is better to imitate ancient than modern work.

While I thought that I was learning how to live, I have been learning how to die.

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.

Man and animals are in reality vehicles and conduits of food, tombs of animals, hostels of Death, coverings that consume, deriving life by the death of others.

Where the spirit does not work with the hand, there is no art.

Knowledge of the past and of the places of the earth is the ornament and food of the mind of man.

Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.

Experience does not err. Only your judgments err by expecting from her what is not in her power.

Tears come from the heart and not from the brain.

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

The greatest deception men suffer is from their own opinions.