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

326 J HOW THE MIND WORKSthought and behavior rather than redescribe it. I think it is unfortunatethat "essentialism" has become an epithet, because at heart it is just theordinary human curiosity to find out what makes natural things work.Essentialism is behind the success of chemistry, physiology, and genetics,and even today biologists routinely embrace the essentialisfc heresywhen they work on the Human Genome Project (but everyone has a differentgenome!) or open up Gray's Anatomy (but bodies vary!).How deeply rooted is essentialist thinking? The psychologists FrankKeil, Susan Gelman, and Henry Wellman have taken the philosophers'thought experiments about natural kinds and given them to children.Doctors take a tiger, bleach its fur, and sew on a mane. Is it a lion or atiger? Seven-year-olds say it's still a tiger, but five-year-olds say it's now alion. This finding, taken at face value, suggests that older children areessentialists about animals but younger ones are not. (At no age are childrenessentialists about artifacts—if you make a coffeepot look like abirdfeeder, children, like adults, say it just is a birdfeeder.)But with deeper probing, one can find evidence for essentialist intuitionsabout living things even in preschoolers. Five-year-olds deny thatan animal can be made to cross the deeper boundary into plants or artifacts.For example, they say that a porcupine that looks as if it has beenturned into a cactus or a hairbrush in fact has not. And preschoolersthink that one species can be turned into another only when the transformationaffects a permanent part of the animal's constitution, notwhen it merely alters appearance. For example, they deny that a lion costumeturns a tiger into a lion. They claim that if you remove the innardsof a dog, the shell that remains, while looking like a dog, is not a dog andcan't bark or eat dogfood. But if you remove the outsides of a dog, leavingsomething that doesn't look like a dog at all, it's still a dog and does doggythings. Preschoolers even have a crude sense of inheritance. Told that apiglet is being raised by cows, they know it will grow up to oink, not moo.Children do not merely sort animals like baseball cards but use theircategories to reason about how animals work. In one experiment, threeyear-oldswere shown pictures of a flamingo, a blackbird, and a bat thatlooked a lot like the blackbird. The children were told that flamingosfeed their babies mashed-up food but bats feed their babies milk, andwere asked what they thought the blackbird feeds its babies. With nofurther information, children went with appearances and said that blackbirds,like bats, give milk. But if they were told that a flamingo is a bird,the children thought of them as working like blackbirds, despite their