History of the Peloponnesian War

The Siceliots indeed, although untrained, might still even now gain the victory, if united in one body. But the Syracusans alone, defeated as they have already been in battle with all their forces, and hemmed in by sea at the same time, will be unable to hold out against the Athenian armament now there.

And if that city is taken, the whole of Sicily also is in their possession, and Italy, too, straightway; and the danger which I just now mentioned as impending from that quarter, would in no long time fall upon you. Let no one then think that he is deliberating about Sicily alone, but about the Peloponnese also, unless you quickly adopt these measures;

unless, I mean, you send thither on board ship such a body of troops, as, after working their own passage, shall immediately act as heavy infantry; and also, what I consider to be still more serviceable than troops, a Spartan as commander, both to discipline their present forces, and to compel those who are unwilling to serve. For so the friends you already have will feel the greater confidence, and those who are doubting between the two sides will more fearlessly join yours. You must also carry on hostilities here in a more decisive manner; that the Syracusans, convinced that you take an interest in them, may offer the greater resistance;