Plato

“Honesty is for the most part less profitable than dishonesty.”

“Astronomy compels the soul to look upwards and leads us from this world to another.”

“He who is of calm and happy nature will hardly feel the pressure of age, but to him who is of an opposite disposition youth and age are equally a burden.”

“Those who intend on becoming great should love neither themselves nor their own things, but only what is just, whether it happens to be done by themselves or others.”

“Those who don't know must learn from those who do.”

“To go to the world below, having a soul which is like a vessel full of injustice, is the last and worst of all the evils.”

“For good nurture and education implant good constitutions.”

“If a man neglects education, he walks lame to the end of his life.”

“The greatest wealth is to live content with little.”

“...[T]he right way is to give one's attention first to the highest good of the young, just as you expect a good gardener to give his attention first to the young plants, and after that to the others. - Socrates”

“Musical training is a more potent instrument than any other, because rhythm and harmony find their way into the inward places of the soul.”

“The gods' service is tolerable, man's intolerable.”

“For this feeling of wonder shows that you are a philosopher, since wonder is the only beginning of philosophy.”

“The excessive increase of anything causes a reaction in the opposite direction.”

“In politics we presume that everyone who knows how to get votes knows how to administer a city or a state. When we are ill... we do not ask for the handsomest physician, or the most eloquent one.”

“Dictatorship naturally arises out of democracy, and the most aggravated form of tyranny and slavery out of the most extreme liberty.”

“The most virtuous are those who content themselves with being virtuous without seeking to appear so.”

“Then the lover, who is true and no counterfeit, must of necessity be loved by his love.”

“Love is the joy of the good, the wonder of the wise, the amazement of the Gods.”

“The learning and knowledge that we have, is, at the most, but little compared with that of which we are ignorant.”