The philosopher John Locke thought we had no innate ideas; our minds are blank slates, upon which experience writes. Nurture is everything, nature nothing. Modern popular genetics gives the impression that we are nothing but the stage on which a play written by our genes is performed; nature is everything, nurture nothing. What are the facts, and what are the philosophical principles that are used to interpret these facts? John and Ken nurture their conversation with Alison Gopnik from UC Berkeley, author of The Scientist in the Crib: What Early Learning Tells Us About the Mind.