Expulsion of the Gelonian dynasty from Syracuse, and of other despots from the other Sicilian towns.—Large changes of resident inhabitants—effects of this fact.—Relative power and condition of the Sicilian cities. Political dissensions at Syracuse. Ostracism tried and abandoned.—Power and foreign exploits of Syracuse.—Sikels in the interior of Sicily—the Sikel prince Duketius—he founds the new Sikel town of Palikê.—Exploits of Duketius—he is defeated and becomes the prisoner of the Syracusans, who spare him, and send him to Corinth.—Duketius breaks his parole and returns to Sicily.—Conquests of Syracuse in the interior of Sicily—death of Duketius.—Prosperity and power of Agrigentum.—Intellectual movement in Sicily—Empedoklês—Tisias—Korax—Gorgias.—Sicilian cities—their condition and proceedings at the first breaking out of the Peloponnesian war, 431 B.C.—Relations of Sicily to Athens and Sparta—altered by the quarrel between Corinth and Korkyra and the intervention of Athens.—Expectations entertained by Sparta of aid from the Sicilian Dorians, at the beginning of the Peloponnesian war. Expectations not realized.—The Dorian cities in Sicily attack the Ionian cities in Sicily.—The Ionic cities in Sicily solicit aid from Athens—first Athenian expedition to Sicily under Lachês.—Second expedition under Pythodôrus.—Indecisive operations near Messênê and Rhegium.—Defeat of the Messenians by the Naxians and Sikels, near Naxos.—Eurymedon and Sophoklês, with a larger Athenian fleet, arrive in Sicily.—Congress of the Sicilian cities at Gela. Speech of Hermokratês.—General peace made between the Sicilian cities. Eurymedon accedes to the peace, and withdraws the Athenian fleet.—Displeasure of the Athenians against Eurymedon and his colleagues.—Intestine dissension in Leontini—expulsion of the Leontine Demos, by the aid of Syracuse.—Application of the Leontine Demos for help to Athens. The Athenians send Phæax to make observations.—Leontini depopulated—the Demos expelled—Leontine exiles at Athens.—War between Selinus and Egesta—the latter applies to Athens for aid.—Promises of the Egestæans: motives offered to Athens for intervention in Sicily.—Alkibiadês warmly espouses their cause, and advises intervention.—Inspecting commissioners despatched by the Athenians to Egesta—frauds practised by the Egestæans to delude them.—Return of the commissioners to Athens—impression produced by their report. Resolution taken to send an expedition to Sicily.—Embarrassment of Nikias as opposer of the expedition.—Speech of Nikias at the second assembly held by the Athenians.—Reply of Alkibiadês.—The assembly favorable to the views of Alkibiadês—adheres to the resolution of sailing to Sicily.—Second speech of Nikias—exaggerating the difficulties and dangers of the expedition, and demanding a force on the largest scale.—Effect of this speech—increased