“A third idea: An infinite range of behavior can be generated by finite combinatorial programs in the mind. Cognitive science has undermined the Blank Slate and the Ghost in the Machine in another way. People can be forgiven for scoffing at the suggestion that human behavior is “in the genes” or “a product of evolution” in the senses familiar from the animal world. Human acts are not selected from a repertoire of knee-jerk reactions like a fish attacking a red spot or a hen sitting on eggs. Instead, people may worship goddesses, auction kitsch on the Internet, play air guitar, fast to atone for past sins, build forts out of lawn chairs, and so on, seemingly without limit. A glance at National Geographic shows that even the strangest acts in our own culture do not exhaust what our species is capable of. If anything goes, one might think, then perhaps we are Silly Putty, or unconstrained agents, after all.”