History of the Peloponnesian War

For the Athenians, much as you are surprised at it, have set out against us with a large force both for sea and land service, nominally, on account of an alliance with the Segestans, and for the purpose of settling the Leontines, but really through desire for Sicily, and most of all, for our city, thinking that if they get this, they will easily get the rest also.

With a conviction, then, that they will quickly be here, consider how with your present resources you may best defend yourselves, and may neither through despising the matter be taken off your guard, nor through disbelieving it neglect the common weal.