WIST

It is the mark of an educated mind to be able to entertain a thought without accepting it.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

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.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

Whatsoever that be within us that feels, thinks, desires, and animates, is something celestial, divine, and, consequently, imperishable.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

The gods, too, are fond of a joke.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

Dignity does not consist in possessing honors, but in deserving them.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

There is no great genius without a touch of madness.

[Nullum magnum ingenium sine mixtura dementiae fuit.]

Aristotle (384-322 BC) Greek philosopher
(Attributed)

Attributed to Aristotle by Seneca the Younger.

Variants:
"No excellent soul is exempt from a mixture of madness."
"No great genius has ever existed without some touch of madness."
"There is no great genius without a mixture of madness."
"There was never a genius without a tincture of madness."

How many a dispute could have been deflated into a single paragraph if the disputants had dared to define their terms?

Aristotle (384-322 BC) Greek philosopher
(Attributed)

There is a foolish corner in the brain of the wisest man.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

Bad men are full of repentance.

Aristotle (384-322 BC) Greek philosopher
(Attributed)

Hence a young man is not a proper hearer of lectures on political science; for he is inexperienced in the actions that occur in life, but its discussions start from these and are about these; and, further, since he tends to follow his passions, his study will be vain and unprofitable, because the end aimed at is not knowledge but action.

Aristotle (384-322 BC) Greek philosopher
Nichomachean Ethics I:3: 1095a2-5

The brave man is the man who faces or fears the right thing for the right purpose in the right manner at the right moment.

Aristotle (384-322 BC) Greek philosopher
Nichomachean Ethics, 3.7 [tr. J. Thomson (1953)]

Anyone can become angry — that is easy, but to be angry with the right person, to the right degree, at the right time, for the right purpose, and in the right way — that is not easy.

Aristotle (384-322 BC) Greek philosopher
Nichomachean Ethics, II.1109a27 (c. 350 BC)

Alt trans.: "Any one can get angry — that is easy — or give or spend money; but to do this to the right person, to the right extent, at the right time, with the right motive, and in the right way, that is not for every one, nor is it easy.

Alt trans.: "The man who gets angry at the right things and with the right people, and in the right way and at the right time, and for the right length of time, is commended."

Alt trans. [J.A.K. Thompson (1953); cited as "2.9"]: "It is easy to fly into a passion -- anybody can do that -- but to be angry with the right person and to the right extent and at the right time and with the right object and in the right way -- that is not easy, and it is not everyone who can do it."

It is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject admits; it is evidently equally foolish to accept probable reasoning from a mathematician and to demand from a rhetorician scientific proofs.

Aristotle (384-322 BC) Greek philosopher
Nicomachean Ethics, I.1094b24 (c. 325 BC)
Alt trans.: "It is the mark of an instructed mind to rest satisfied with the degree of precision which the nature of the subject admits and not to seek exactness where only an approximation is possible."

It is not always the same thing to be a good man and a good citizen

Aristotle (384-322 BC) Greek philosopher
Nicomachean Ethics (325 BC)

We are what we repeatedly do. Excellence, therefore, is not an act but a habit.

Aristotle (384-322 BC) Greek philosopher
Nicomachean Ethics (c. 350 BC) (paraphrase)

Alt.: "We are what we repeatedly do. Excellence, then, is not an act, but a habit."

Alt.: "We are what we repeatedly do, therefore excellence is not an act, but a habit."

Not actually Aristotle, but a summary by  Will Durant,  The Story of Philosophy: The Lives and Opinions of the World's Greatest Philosophers (1926), ch. II "Aristotle and Greek Science," Part VII "Ethics and the Nature of Happiness" (1926):

Excellence is an art won by training and habituation: we do not act rightly because we have virtue or excellence, but we rather have these because we have acted rightly; 'these virtues are formed in man by his doing the actions'; we are what we repeatedly do. Excellence, then, is not an act but a habit: 'the good of man is a working of the soul in the way of excellence in a complete life... for as it is not one swallow or one fine day that makes a spring, so it is not one day or a short time that makes a man blessed and happy.'"

The quoted phrases are from the Nicomachean Ethics, Book II, 4; Book I, 7.

For though we love both the truth and our friends, piety requires us to honor the truth first.

Aristotle (384-322 BC) Greek philosopher
Nicomachean Ethics, bk. 1, ch. 6 (I.1096a16) [tr. T. Irwin (1985)]
Alt trans.: "Piety requires us to honor truth above our friends."

The generality of men are naturally apt to be swayed by fear rather than reverence, and to refrain from evil rather because of the punishment that it brings than because of its own foulness.

Aristotle (384-322 BC) Greek philosopher
Nicomachean Ethics, bk. 10, ch. 9

The least initial deviation from the truth is multiplied later a thousandfold.

Aristotle (384-322 BC) Greek philosopher
On the Heavens, Book I, ch. v

Such an event is probable in Agathon’s sense of the word: “It is probable,” he says, “that many things should happen contrary to probability.”

Aristotle (384-322 BC) Greek philosopher
Poetics, ch. 18

Well begun is half done.

Aristotle (384-322 BC) Greek philosopher
Politics, V.1303b30 (c. 350 BC)
Quoting a proverb.

A tyrant must put on the appearance of uncommon devotion to religion. Subjects are less apprehensive of illegal treatment from a ruler whom they consider god-fearing and pious. On the other hand, they do less easily move against him, believing that he has the gods on his side.

Aristotle (384-322 BC) Greek philosopher
Politics, V.1314b39

It is deliberate purpose that constitutes wickedness and criminal guilt.

Aristotle (384-322 BC) Greek philosopher
Rhetoric, 1.13 [tr. W. Rhys Roberts (1954)]
Often given as "The intention makes the crime."