He was the first to create a wide-ranging system of thought that included morality and aesthetics, logic and science, politics and metaphysics.
Here are some profound quotes from his broad and diverse works.
It is the mark of an educated mind to be able to entertain a thought without accepting it.
All men by nature desire to know.
Excellence is an art won by training and habituation. We do not act rightly because we have virtue or excellence, but we rather have those because we have acted rightly. We are what we repeatedly do. Excellence, then, is not an act but a habit.
The roots of education are bitter, but the fruit is sweet.
He who is unable to live in society, or who has no need because he is sufficient for himself, must be either a beast or a god.
I count him braver who overcomes his desires than him who overcomes his enemies.
Fear is pain arising from the anticipation of evil.
Pleasure in the job puts perfection in the work.
All paid jobs absorb and degrade the mind.
Nature does nothing uselessly.
Anybody can become angry - that is easy, but to be angry with the right person and to the right degree and at the right time and for the right purpose, and in the right way - that is not within everybody's power and is not easy.
To enjoy the things we ought and to hate the things we ought has the greatest bearing on excellence of character.
Bring your desires down to your present means. Increase them only when your increased means permit.
We make war that we may live in peace.
Man is by nature a political animal.
The basis of a democratic society is liberty.
The best political community is formed by citizens of the middle class.
Dignity consists not in possessing honors, but in the consciousness that we deserve them.
Humor is the only test of gravity, and gravity of humor; for a subject which will not bear raillery is suspicious, and a jest which will not bear serious examination is false wit.
We become just by performing just action, temperate by performing temperate actions, brave by performing brave action.
We are what we repeatedly do.
Man perfected by society is the best of all animals; he is the most terrible of all when he lives without law, and without justice.
Change in all things is sweet.
Courage is a mean with regard to fear and confidence.
Courage is the first of human qualities because it is the quality which guarantees the others.
Education is the best provision for old age.
The educated differ from the uneducated as much as the living from the dead.
Every art and every inquiry, and similarly every action and choice, is thought to aim at some good; and for this reason the good has rightly been declared to be that at which all things aim.
All human actions have one or more of these seven causes: chance, nature, compulsions, habit, reason, passion, desire.
At his best, man is the noblest of all animals; separated from law and justice he is the worst.
Bad men are full of repentance.
Misfortune shows those who are not really friends.
One swallow does not make a summer.
With regard to excellence, it is not enough to know, but we must try to have and use it.
He who hath many friends hath none.
It is best to rise from life as from a banquet, neither thirsty nor drunken.
Suffering becomes beautiful when anyone bears great calamities with cheerfulness, not through insensibility but through greatness of mind.
The ideal man bears the accidents of life with dignity and grace, making the best of circumstances.