The Eight Books of Thucydides' History, translated by R. Crawley.
Nicias spoke positively because he had exact information of the financial distress at Syracuse, and also because of the strength of the Athenian party there which kept sending him messages not to raise the siege; besides which he had more confidence than before in his fleet, and felt sure at least of its success. Demosthenes, however, would not hear for a moment of continuing the siege, but said that if they could not lead off the army without a decree from Athens, and if they were obliged to stay on, they ought to remove to Thapsus or Catana; where their land forces would have a wide extent of country to overrun, and could live by plundering the enemy, and would thus do them damage; while the fleet would have the open sea to fight in, that is to say, instead of a narrow space which was all in the enemy's favour, a wide sea-room where their science would be of use, and where they could retreat or advance without being confined or circumscribed either when they put out or put in. In any case he was altogether opposed to their staying on where they were, and insisted on removing at once, as quickly and with as little delay as possible; and in this judgment Eurymedon agreed. Nicias however still objecting, a certain diffidence and hesitation came over them, with a suspicion that Nicias might have some further information to make him so positive.
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