History of the Peloponnesian War

For when the Athenians had come to this country, for the subjugation of Sicily in the first place, and then, if they succeeded, for that of the Peloponnese also, and the rest of Greece; and when they possessed the largest empire enjoyed hitherto, either by Greeks of former times or of the present, you were the first men in the world who withstood their navy, with which they had borne down every thing, and have already conquered them in some sea-fights, and will now, in all probability, conquer them in this.

For when men have been put down in that in which they claim to excel, their opinion of themselves in future is far lower than if they had never entertained such an idea at first; and failing through the disappointment of their boasting, they give way even beyond the degree of their power. And such, probably, is now the feeling of the Athenians.

"But in our case, both the opinion we entertained before, and with which, even while we were yet unskilful, we were full of daring, has now been confirmed; and from the addition to it of the thought that we must be the best seamen in the world, since we have conquered the best, each man's hope is doubled. And, generally speaking, it is the greatest hope that supplies also the greatest spirit for undertakings.