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.
And when the Mantineans had revolted, the rest of the Peloponnesus also began to mutter that they must do the like, thinking that the Mantineans had changed sides because they possessed some superior knowledge. At the same time they were angry with the Lacedaemonians on other grounds, and especially because it was written in the treaty with Athens that it would be consistent with their oaths to add or take away whatever shall seem good to both states, that is, to the Lacedaemonians and Athenians.
For it was this article especially that was disturbing the Peloponnesus far and wide and causing suspicion that the Lacedaemonians wished in concert with the Athenians to reduce them all to slavery; for it would have been just, they thought, that the clause should have given the power to alter the articles to all the allies.
And so most of them were afraid and were eager on their own part also to make a separate alliance with the Argives.
The Lacedaemonians, aware of this murmuring that was going on in the Peloponnesus, and that the Corinthians had been the instigators in this matter and were themselves going to make a treaty with Argos, sent envoys to Corinth, wishing to forestall what was about to happen. And they charged them with starting the whole movement, and said that if they should revolt from them and become allies of the Argives, they would be violating the explicit terms of their oaths, and indeed were already doing wrong in not accepting the treaty with the Athenians, inasmuch as it had been declared that whatever the majority of the allies decreed should be binding, unless there should be some hindrance on the part of gods or heroes.
But the Corinthians, in the presence of all their allies who had not themselves accepted the treaty—for they had on their own responsibility summoned them beforehand— in reply to the Lacedaemonians said in what respects they had been wronged, not stating outright that the Lacedaemonians had failed to recover from the Athenians for them Sollium[*](In Acarnania, taken by the Athenians in the first year of the war (2.30.1).) or Anactorium,[*](cf. 4.49.) nor mentioning any other matter in which they thought they were getting less than their rights, but making a pretext that they could not give up their allies in Thrace; for they said they had given their oaths to these people, both privately, when they had first revolted along with the Potidaeans,[*](cf. 1.58.1.) and afterwards.
They were therefore, they said, not violating their oaths to their allies by refusing to join in the treaty with the Athenians; for since they had bound themselves to those allies by pledges sworn in the name of the gods, it would not be consistent with their oaths to betray them.
Besides, the words of the agreement were, “if there be no hindrance on the part of gods or heroes”; and it seemed to them that this was a hindrance on the part of the gods.