This chapter shows how “the Hobbesian hypothesis” (the claim that everyone is better off in a state society with a private property system than they could reasonably expect to be in any society without either of those institutions) appeared in Nineteen-Century Political Theory. As in the Eighteen Century, disagreement about the truth of the hypothesis produced virtually no debate. G. W. F. Hegel, Frédéric Bastiat, and others asserted it with very little supporting evidence. Henry David Thoreau, Herbert Spencer, Henry George, Karl Marx, Friedrich Engels, John Robert Seeley, Henry Sidgwick, Henry Sumner Maine, and Peter Kropotkin all voiced various levels of scepticism, and some, especially Kropotkin, produced considerable evidence. Yet supporters went on asserting the hypothesis as if it were an unchallengeable and obvious truth.