Steven Pinker -- How the Mind Works - Hampshire High Italian ...

430 I HOW THE MIND WORKSnonrelatives, so if a gene makes an organism benefit a relative (say, byfeeding or protecting it), it has a good chance of benefiting a copy ofitself. With that advantage, genes for helping relatives will increase in apopulation over the generations. The vast majority of altruistic acts in theanimal kingdom benefit the actor's kin. The most extreme examples ofkin-directed altruism are found among social insects like ants and bees,in which the workers give their all to the colony. They are permanentlysterile and defend the colony with kamikaze tactics like blowing up tospray noxious chemicals on an invader or stinging it with a barbed stingerthat pulls the insect's body apart when dislodged. Such dedication comeslargely from an unusual genetic system which makes them more closelyrelated to their sisters than they would be to their offspring. By defendingthe colony they help their mothers make sisters instead of makingoffspring of their own.Genes can't call to one another or pull the strings of behavior directly.In humans, "kin altruism" and "benefiting one's genes" are shorthand fortwo collections of psychological machinery, one cognitive, one emotional.Humans are equipped with a desire and an ability to learn their familytree. Genealogy is a special kind of knowledge. First, the relationshipsare digital. You're either someone's mother or you aren't. You might beeighty percent sure that Bill is John's father, but that is not the same asthinking that Bill is eighty percent of a father to John. We speak of halfbrothers,but everyone knows the expression is shorthand for having thesame mother and different fathers or vice versa. Second, kinship is arelation. No one is a father or a sister, period; they have to be the fatheror the sister of someone. Third, kinship is topological. Everyone is a nodein a web whose links are defined by parenthood, generation, and gender.Kinship terms are logical expressions that are read off the geometry andlabeling of the web: a "parallel cousin," for example, is one's father'sbrother's child or one's mother's sister's child. Fourth, kinship is self-contained.Age, place of birth, acquaintanceship, status, occupation, zodiacsign, and all the other categories in which we place people lie in a differentplane from the categories of kinship and need not be consulted whenwe calculate kinship.Homo sapiens is obsessed with kinship. All over the world, when peopleare asked to talk about themselves, they begin with their parentageand family ties, and in many societies, especially foraging groups, peoplerattle off endless genealogies. For adoptees, childhood refugees, or