Thucydides

"The truth is like a lion; you don't have to defend it. Let it loose; it will defend itself."

"Change is the only constant in life."

"The educated differ from the uneducated as much as the living differ from the dead."

"The greatest enemies are our own treacherous desires."

"People who have known each other their whole lives are sometimes killed one by another in wars."

"Of all the powers operating in nature, I am convinced that the most wonderful is that of habit."

"Misfortune sours us against the world, and especially against those who have not shared it."

"The great king of Sparta knows that life is not measured by the number of our days, but by the deeds and impacts of those days."

"To do as you would be done by, and to treat others as yourself would wish to be treated is the foundation of justice."

"The richest and most powerful nations are not always the wisest."

"Time is the judge of all things."

"Those who truly wish for peace must prepare for war."

"Envy is the ulcer of the soul."

"The wise learn from the mistakes of others; fools from their own."

"It is a great thing to know the season for something and when to refrain from it."

"What we leave behind is not as important as how we live."

"The human mind is not capable of grasping the universe."

"Innovation distinguishes a forward thinking people from those bound by tradition."

"The path to wisdom begins with understanding our own ignorance."

"Fear makes men cruel rather than kind."

"In the arena of human life, the honors and rewards fall to those who show their good qualities in action."

"A state is as the ruler makes it."

"The love of money is a disease, but not one that makes men unhappy."

"Men are slow to believe that which would hurt them if believed."

"War is a continuation of politics by other means."

"The secret of being free is being brave."

"Those who dare to teach must never cease to learn."

"In a calm sea, every man is a pilot, but in a storm we discover who the real sailors are."

"The same thing happens to all nations: when they become strong they become arrogant."

"Misery in a state is that which is willed to be created."