The conventional wisdom in the social sciences is that human nature is simply the imprint of an individual's background and experience. But our cultures are not random collections of arbitrary habits. They are canalized expressions of our instincts. That is why the same themes crop up in all cultures - themes such as family, ritual, bargain, love, hierarchy, friendships, jealousy, group loyalty, and superstition. That is why, for all their superficial differences of language and custom, foreign cultures are still immediately comprehensible at the deeper level of motives, emotions and social habits. Instincts, in a species like the human one, are not immutable genetic programs; they are pre-dispositions to learn. And to believe that human beings have instincts is no more determinist than to believe they are the products of their upbringing.
- Matt Ridley, "The Origins of Virtue"