The interdisciplinary field of cognitive science brings together computer models from Artificial Intelligence and experimental techniques from cognitive psychology to try to construct precise and testable theories of the workings of the human mind. And if we are going to say that a given program thinks like a human being, we must have some way of determining how human beings think. For that, we need to get inside the actual workings of the human mind. Stuart Russell and Peter Norvig say, “there are two ways to do this: through introspection–trying to catch our own thoughts as they go by –or through psychological experiments. Once we have a sufficiently precise theory of the mind, it becomes possible to express the theory as a computer program. If the program’s input/output and timing behavior matches human behaviour, that is evidence that some of the program’s mechanisms may also be operating in humans.”¹²