[Among] prehistoric men . . . life was a continual free fight, and beyond the limited and temporary relations of the family, the Hobbesian war of each against all was the normal state of existence.
T. H. Huxley,The Struggle for Existence: A Programme (1888) p. 163
The philosophers . . . have all felt it necessary to go back to the state of nature, but none of them has succeeded in getting there.
J.-J. Rousseau,Discourse on the Origins and Foundationsof Inequality Among Men (1755) p. 1
Could strong reciprocity, fair-mindedness, and other altruistic and ethical preferences documented in Chapter 3 be the legacy of an evolutionary past in which individuals behaving in these ways had higher fitness than they would have had ...