History of the Peloponnesian War

"If there be any dispute on the part of any one of the cities, either of those within the Peloponnesus or without, whether about boundaries or anything else, the matter shall be judicially decided. But if any city of the allies quarrel with another, they shall appeal to some city which both deem to be impartial. 5. “Individual citizens shall conduct their suits according to hereditary usage.”

Such was the treaty and alliance that was concluded; and all the places which either side had acquired from the other in war they restored, or if there was any other ground of difference between them, they came to an agreement about it. Acting now in concert in their affairs, they voted not to receive herald or embassy from the Athenians, unless they evacuated their forts and withdrew from the Peloponnesus;

also not to make peace or carry on war with anyone except together. And not only did they prosecute other matters with energy, but both of them sent envoys to the places in Thrace and to Perdiccas. And they persuaded Perdiccas to swear alliance with them. He, however, did not desert the Athenians at once, but was thinking of it, because he saw the Argives had done so; for he was himself of Argive descent.[*](cf. 2.99.3.)