this can be the case, Armstrong describes a method by which a psychologist may determine whether an animal can distinguish between two colours by training it to perform a task that requires this perception. The animal's behaviour would indicate its perception of the colours. While a Behaviourist would say that the animal's behaviour was its perception, Armstrong describes the perception as a state of the animal's mind. It is implied that one could test for consciousness using a similar method. Further illustrating his idea, Armstrong gives an analogy in which perception is a key to a door, the door being action. The unlocking of the door, and therefore action, is optional, but one cannot open the door without the key. A blind man, for instance, lacks certain keys. As a result, he cannot operate in an environment in the same way that a sighted man can. Using this conception of perception as a state, Armstrong characterizes consciousness as "perception or awareness of the state of our own mind", or "a self-scanning system in the central nervous system". He sees consciousness not as an external construct that interacts with the body and brain, but a self-aware state of the physical brain. Publishing history The Nature of Mind and Other Essays, University of Queensland Press, 1980. .The Nature of Mind and Other Essays, Harvester Press, 1981. .The Nature of Mind and Other Essays'', Cornell University Press, 1981. . Notes and citations References Contemporary philosophical literature Philosophy books Philosophy of mind literature Materialism 1980 essays University of Queensland Press books