Indicates that research in social psychology has largely been based on college students tested in academic laboratories on academiclike tasks. How this dependence on one narrow data base may have biased the main substantive conclusions of sociopsychological research in this era is discussed. Research on the full life span suggests that, compared with older adults, college students are likely to have less crystallized attitudes, less formulated senses of self, stronger cognitive skills, stronger tendencies to comply with authority, and more unstable peer-group relationships. These peculiarities of social psychology's predominant data base may have contributed to central elements of its portrait of human nature. According to this view, people are quite compliant and their behavior is easily socially influenced, readily change their attitudes and behave inconsistently with them, and do not rest their self-perceptions on introspection. The data base may also contribute to this portrait of human nature's strong emphasis on cognitive processes and to its lack of emphasis on personality dispositions, material self-interest, emotionally based irrationalities, group norms, and stage-specific phenomena. The analysis implies the need both for more careful examination of sociopsychological propositions for systematic biases introduced by dependence on this data base and for increased reliance on adults tested in their natural habitats with materials drawn from ordinary life. (127 ref)