History of the Peloponnesian War

"We are not unaware, men of Lacedaemon and members of the alliance, of the traditional feeling of the Hellenes towards men who revolt in time of war and abandon their former alliance: those who accept them as allies are indeed pleased with them in so far as they derive advantage, but they regard them as traitors to their former friends and therefore think the worse of them.

And this estimate is not unjust, provided that those who revolt and those from whom they secede held the same political views and were actuated by the same feeling of good will toward one another, and were evenly matched in preparation for war and in power, and provided also that there were no reasonable excuse for their revolt. But these conditions did not obtain between us and the Athenians;

therefore, let no one think the worse of us on the ground that we were honoured by them in time of peace and now revolt from them in time of danger.