ABSTRACT
Almost every human act is unique: a precise and complete physical description of it would yield measurements that differed, at least to some small degree, from the complete description of any other act, even one that was extremely similar. When a person says hello, the sound pattern is relatively idiosyncratic: it can be distinguished from the sound patterns for that greeting as spoken by other people. But two such sound patterns from the same person will typically differ in inflection, enthusiasm, or warmth, as well as in length, pitch, or loudness, these differences having some associations with the person greeted, the setting, and other conditions. In this chapter we shall consider such specificity—its sources and its effects on measurements. Involved in this discussion will be the reactions of subjects to tests (examined in the preceding chapter) and the stability-instability of behavior, which was the topic of Chapter 9. The problem of specificity has been raised not only toward the end of Chapter 2 but also, more or less directly, in almost every subsequent chapter.
