bivalence, principle of See PRINCIPLE OF BIVA -. LENC. black box, a hypothetical unit specified only by functional role, in order to explain some effect or behavior. The term may refer to a single entity with an unknown structure, or unknown internal organization, which realizes some known function, or to any one of a system of such entities, whose organization and functions are inferred from the behavior of an organism or entity of which they are constituents.
Within behaviorism and classical learning theory, the basic functions were taken to be generalized mechanisms governing the relationship of stimulus to response, including reinforcement, inhibition, extinction, and arousal. The organism was treated as a black box realizing these functions. Within cybernetics, though there are no simple input–output rules describing the organism, there is an emphasis on functional organization and feedback in controlling behavior. The components within a cybernetic system are treated as black boxes. In both cases, the details of underlying structure, mechanism, and dynamics are either unknown or regarded as unimportant.
See also BEHAVIORISM , PHILOSOPHY OF MIND , THEORETICAL TER. R.C.R.