ABSTRACT
Control of Boiotia, and the central Greek land empire generally, was lost to Athens in 446 as part of Pericles' deal with Pleistoanax. But her command of the eastern seas was unimpaired, as is proved by the free hand she enjoyed in suppressing revolt on Samos in 440/39. Thucydides narrates the events of the next decade not as part of the 'Fifty Years', to which they strictly belong, but as part of the sequence of events which immediately caused the great Peloponnesian War. The Fifty Years, in the historian's causal scheme, were the underlying cause of the war, which Thucydides saw as the process of Athenian aggrandizement which struck fear into Sparta. This is the 'truest cause' ofThuc. i.23, a famous and deeply original statement which is the first conscious attempt to develop a theory of historical causation: 'The truest cause', he says, 'was one not much admitted at the time: it was the growth ofAthenian power, which frightened the Spartans and forced them to war. But the publicly alleged reasons were as follows ... ' and Thucydides goes on to give them: quarrels between Athens and Corinth over Corcyra and Potidaia. Elsewhere in book i (chapter 118) Thucydides closes the Fifty Years by speaking of Athens' power 'rising to a peak plain for all to see', and of Athens 'encroaching on Sparta's allies'.
