 The best available science today (including evolutionary theory and psychology) supports rather than undermines the ancient Greek assumption that we are social animals, like elephants and wolves and unlike polar bears. No rationalizing explanation in terms of anything like a social contract is needed to explain why we choose to live together, subjugating our egoistic desires in order to secure the advantages of co-operation. Like other social animals, our natural impulses are not solely directed towards our own pleasures and preservation, but include altruistic and cooperative ones.