What can we know of human knowledge or understand about human understanding? The very reflexiveness of the questions can make us chase our own tails for a starting point. As this book is concerned with the acquisition of knowledge, the knowledge that things are the case, there seem to be at least two main starting points, one psychological and the other philosophical. Psychologists interested in the genetic psychology of cognition study the processes of coming to know in the human child, at the most general level the way in which biological and experiential factors interact to produce and maintain this development. Philosophers who study the theory of knowledge, or epistemology, wish to determine the status, extent and character of knowledge in the individual and/or the scientific community.