It was impossible for any one to open his grief to a neighbor and to concert measures to defend himself, as he would have had to speak either to one whom he did not know, or whom he knew but did not trust.

Thucydides, The History of the Peloponnesian War

Love of country is what I do not feel when I am wronged, but what I felt when secure in my rights as a citizen.... the true lover of his country is not he who consents to lose it unjustly rather than attack it, but he who longs for it so much that he will go all lengths to recover it.

Alcibiades, as quoted by Thucydides, (The History of the Peloponnesian War)

Athenians: Aim at what is feasible, holding in view the real sentiments of us both; since you know as well as we do that right, as the world goes, is only in question between equals in power, while the strong do what they can and the weak suffer what they must....

Melians: As we think, at any rate, it is expedient —we speak as we are obliged, since you enjoin us to let right alone and talk only of interest— that you should not destroy what is our common protection, the privilege of being allowed in danger to invoke what is fair and right, and even to profit by arguments not strictly valid if they can be got to pass current....

Athenians:  Of the gods we believe, and of men we know, that by a necessary law of their nature they rule wherever they can.....  It is certain that those who do not yield to their equals, who keep terms with their superiors, and are moderate towards their inferiors, on the whole succeed best.

  Thucydides (Book Five), The History of the Peloponnesian War

Ordinary men usually manage public affairs better than their more gifted fellows. The latter are always wanting to appear wiser than the laws, and to overrule every proposition brought forward, thinking that they cannot show their wit in more important matters.

 Thucydides (Book Three), The History of the Peloponnesian War

[Pericles] told them to wait quietly, to pay attention to their marine, to attempt no new conquests, and to expose the city to no hazards during the war, and doing this, promised them a favourable result. What they did was the very contrary, allowing private ambitions and private interests, in matters apparently quite foreign to the war, to lead them into projects unjust both to themselves and to their allies— projects whose success would only conduce to the honour and advantage of private persons, and whose failure entailed certain disaster on the country in the war.... each grasping at supremacy, they ended by committing even the conduct of state affairs to the whims of the multitude.

Thucydides, The History of the Peloponnesian War

Your country has a right to your services in sustaining the glories of her position. These are a common source of pride to you all, and you cannot decline the burdens of empire and still expect to share its honors. You should remember also that what you are fighting against is not merely slavery as an exchange for independence, but also loss of empire and danger from the animosities incurred in its exercise. Besides, to recede is no longer possible.... For what you hold is, to speak somewhat plainly, a tyranny; to take it perhaps was wrong, but to let it go is unsafe.

Pericles, as quoted by Thucydides in  The History of the Peloponnesian War

The Athenians are addicted to innovation, and their designs are characterized by swiftness alike in conception and execution.... they are adventurous beyond their power, and daring beyond their judgment, and in danger they are sanguine.... they are never at home.... they were born into the world to take no rest themselves and to give none to others.

Thucydides, The History of the Peloponnesian War  (Translated by Richard Crawley; Book 1, Chapter 3)