Thucydides was the first ancient Greek historian to double as a social scientist. He set out to understand human events entirely in human terms, without recourse to myth. He sought to know why people go to war and how they are affected by its violence. He studied the civil war in Corcyra, which began when radicals burst into the council house and killed leaders who favored democracy. The strengths and weaknesses of democracy are a major theme of his History. Its larger story shows how the Athenians tried to expand their empire too far and came to a crushing defeat. Here are vivid stories of land and sea battles, interspersed with fascinating and disturbing debates about war and policy. All of Thucydides's History is here, either in summary or translation, in a volume short enough for a wide readership. This Second Edition is expanded to include all the important debates and battle scenes, and the entire translation has been revised in accord with the latest scholarship. The Essential Thucydides (Hackett, fall 2021) is the second edition of Paul Woodruff's On Justice, Power, and Human Nature: Selections from The History of the Peloponnesian War (first published by Hackett Publishing Company in 1993, paperback ISBN 978-0-87220-168-2, cloth ISBN 978-0-87220-169-9).