One of the most fundamental questions social psychologists have addressed within the past 50 years is that of why people have attitudes, that is, why we evaluate the people, objects, and events we encounter in terms of whether they are “good” or “bad.” What purpose or purposes do attitudes serve? How might the evaluation of objects facilitate effective adaptation to, and functioning within, our physical and social worlds? In their seminal treatment of this subject, Smith and his colleagues (Smith, 1947; Smith, Bruner, & White, 1956) emphasized the object appraisal function of attitudes, which enables people to categorize entities as either conducive or nonconducive to their goals and objectives, as a prelude to

behaving toward those entities. From this perspective, attitudes provide a basis for taking action that is personally adaptive, which leads people to approach entities that are beneficial and to avoid entities that are harmful. Subsequently, Katz (1960) distinguished between what he termed the knowledge function of attitudes, which emphasizes their role in cognitively structuring and organizing the barrage of information in the stimulus environment, and the instrumental or utilitarian function of attitudes, by which attitudes provide guidance in maximizing rewards and minimizing punishments. These early theoretical insights into attitude function have withstood the test of time, enjoying considerable support among contemporary researchers and theorists. Although other important attitude functions, such as social adjustment, value expression, and ego defense, continue to be of great interest (see Pratkanis, Breckler, & Greenwald, 1989), many writers consider object appraisal (and its constituent instrumental and knowledge functions) to be the universal or master function of all attitudes (Eagly & Chaiken, 1998; Fazio, 1989, Greenwald, 1989).