Behavior evolves through natural selection, just as anatomy does. Hence if sex is enjoyable, natural selection must have been responsible for that ou… - Jared Diamond

Perhaps we could benefit by selectively adopting some of those traditional practices. Some of us already do so, with demonstrated benefits to our health and happiness. In some respects we moderns are misfits; our bodies and our practices now face conditions different from those under which they evolved, and to which they became adapted. But we should also not go to the opposite extreme of romanticizing the past and longing for simpler times. Many traditional practices are ones that we can consider ourselves blessed to have discarded — such as infanticide, abandoning or killing elderly people, facing periodic risk of starvation, being at heightened risk from environmental dangers and infectious diseases, often seeing one’s children die, and living in constant fear of being attacked. Traditional societies may not only suggest to us some better living practices, but may also help us appreciate some advantages of our own society that we take for granted.

The societies to which most readers of this book belong represent a narrow slice of human cultural diversity. Societies from that slice achieved world dominance not because of a general superiority, but for specific reasons: their technological, political, and military advantages derived from their early origins of agriculture, due in turn to their productive local wild domesticable plant and animal species. Despite those particular advantages, modern industrial societies didn’t also develop superior approaches to raising children, treating the elderly, settling disputes, avoiding non-communicable diseases, and other societal problems. Thousands of traditional societies developed a wide array of different approaches to those problems.

As we shall see in this book's chapters, traditional societies are far more diverse in many of their cultural practices than are modern industrial societies. [...] Yet psychologists base most of their generalizations about human nature on studies of our own narrow and atypical slice of human diversity. [...] That is, as social scientists Joseph Henrich, Steven Heine, and Ara Norenzayan express it, most of our understanding of human psychology is based on subjects who may be described by the acronym WEIRD: from Western, educated, industrialized, rich, and democratic societies. [...] Hence if we wish to generalize about human nature, we need to broaden greatly our study sample from the usual WEIRD subjects [...] to the whole range of traditional societies.