History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
The Athenians came against this country in the first place for the enslavement of Sicily, and after that, if they should be successful, for that of the Peloponnesus also and the rest of Hellas, having already acquired a dominion greater than that of any Hellenes either of the past or of the present time; but you, the first men who ever withstood their fleet, with which they had obtained the mastery everywhere, have already defeated them on the sea and in all probability will defeat them in this present battle.
For when men have once suffered abatement just where they claim to be superior, what is left of their self-esteem is weaker than it ever was —than if they had never thought themselves superior at all—and their pride being mortified by the disappointment,[*](Or “unexpectedly deceived in their self-confidence.”) they give way out of all proportion to their actual strength. And at the present moment this is what the Athenians have probably suffered.
"With us, however, the feeling that before animated us, which led us, even though we were inexperienced, to venture our all, is now more fully confirmed; and since there has been added to it the conviction that we are strongest, because we have defeated the strongest, the hope of each man is doubled. And, generally speaking, the greatest hope inspires in men the greatest zeal for their undertakings.