Leviathan

Hobbes wrote out of the fear of civil war, and he was honest about it. Without a strong common power, he argued, life is a war of all against all, and almost any order is better than that. It is a bleak foundation, and nearly everyone who came after argued against it. But that is the point: Leviathan is the book the whole modern tradition had to answer first. To disagree well with Hobbes is to begin to understand why the state exists at all.

The Englishman who wrote political theory out of fear, and was honest about it. Living through civil war, he concluded that life without a strong common power was a war of all against all, and that almost any order was better than that. Leviathan is the starting gun for modern political thought. Nearly everyone who came after, including those who despised his conclusions, had to argue against him first. That is the mark of a foundational book.