Chapter Three

There has been a growing trend in developmental psychology to regard children as possessed of theories and to regard at least some of their cognitive development as similar to processes of theory change in science (Gopnik and Meltzoff 1997; Wellman 1990; Carey 1985; Perner 1991b; Kitcher 1988). Some proponents of this trend in developmental psychology have attempted to make clear exactly what they mean when they say of a child that she has a “theory,” but they have found only limited help in the philosophy of science: The standard philosophical accounts of theories are not well-suited to the discussion of non-technical, everyday theories of the kind it is reasonable to think children might have. Psychologists have thus been forced into the position of developing their own accounts of what a theory is -a useful and rewarding task, no doubt, but one matching more closely the job description of philosophers than psychologists. In this chapter, I will attempt to remedy this failure of philosophy of science to come to the aid of an actual science in need. Specifically, I will offer an account of theories that -unlike the accounts currently on offer in philosophy of science applies equally well to technically sophisticated scientific