History of the Peloponnesian War
Thucydides
Thucydides. The history of the Peloponnesian War, Volume 1-2. Dale, Henry, translator. London: Heinemann and Henry G. Bohn, 1851-1852.
Besides, they were also afraid of their allies, lest they should be encouraged by their reverses to revolt on a larger scale; and they repented not having come to an arrangement, when they had a fine opportunity, after the events at Pylus.
The Lacedaemonians, on the other hand, wished for peace, because they found protracted beyond their expectation those hostilities by which they imagined that in a few years they should reduce the power of the Athenians, if they ravaged their land; and because they had met with the disaster on the island—such as had never yet befallen Sparta: and in consequence of their country being plundered from Pylus and Cythera; while their helots also were deserting, and there was a constant apprehension lest even those that remained in the country, trusting in the support of those who were out of it, should, on the strength of the present state of things, adopt some revolutionary designs against them, as on a former occasion.