ABSTRACT
This chapter argues that a major function of the human brain is indeed to sustain complex structures of knowledge of the physical world, and also of plans and purposes in the social world. It explores the ideas of mental schemata and metaphor, to create some metaphors from technology and computing, including the metaphor of representation. The metaphor proper, however, only comes into its own in human thinking. The chapter includes metaphors to reach out towards abstract ideas of representation: clocks as models of terrestrial rotation, the projection of schemata or theories onto evidence to describe perception. These three stages, simple representation, perception and understanding, can be thought of as stages of evolutionary emergence. In trying to understand the self-reflective consciousness, computational metaphors start to fail. With the possible exception of Sussman's program, which simulates learning a skill in a program that rewrites parts of itself in response to its mistakes, metaphors from the computational domain cease to be adequate.
