ABSTRACT
Boring puts the matter well, "A stone is shape, color, weight, and kind of substance in complicated relation. When such descriptive ulti-mates are general properties which can vary continuously or discretely, when they are, in short, parameters, they may, if one chooses, be called attributes of the object described". The distinction between defining attributes and criterial attributes is essential to all of the discussion that is to follow. For it permits think of categorizing as a process of achievement: discovering the defining attributes of the environment so that they may serve with their proper values as the criteria for making judgments about identity. Tolman and Brunswik speak of the "causal texture of the environment" to refer to the probability with which cues or signals point to their referents. Information theorists speak of causal texture as the redundancy of an input and speak of the transitional or contingent probability that characterizes the occurrence of two stimulus events.
