Relational Approach to Personality Development 1 Mascolo, M. F. (2020). One person, many selves: A relational-developmental conception of self and personality development. In M. F. Mascolo & T. Bidell (Eds.) Handbook of Integrative Psychological Development (pp. 325-356). Routledge/Taylor & Francis. ONE PERSON, MANY SELVES: A RELATIONAL-DEVELOPMENTAL CONCEPTION OF SELF AND PERSONALITY Michael F. Mascolo Merrimack College For better and for worse, during the first half of the twentieth century, personality psychology was organized around the elaboration of “grand theories” – broad-based models intended to explain the nature of persons and their functioning (Hall & Lindzey, 1957). Such models were comprehensive in nature, and sought to address central questions such as the anatomy of psychological functioning, the nature human motivation, the role of conscious and nonconscious processes in psychological activity, the origins of individual differences in patterns of individual action, the development of personality structures, and so forth. Different theoretical systems were founded upon diverse philosophical, theoretical and methodological frameworks. However, because they were often couched in general terms that could not easily be specified or falsified, scientific progress was limited. As grand theories proliferated, theorists and researchers increasing found themselves working within encased assumptive frameworks that limited the capacity for cross-theoretical exchange and scientific progress. Under such circumstances, nothing approximating an integrative model of personhood (Paranjpe, 1998) or personality (Mischel, 2004) could emerge. Interest in grand theorizing began to wane, and researchers began to focus their energies on more local problems in the study of personality processes (McKinney, 1978). With the collapse of grand theorizing, researchers began to pursue questions that could more easily lend themselves to empirical analysis. In so doing, psychologists turned their attention to what is typically understood as the core focus of personality theory – namely, the questions related to the stability and consistency of individual behavior (Mischel, 1982). Even during the period of grand theorizing, personality theorists often invoked the concept of trait to account for stability and consistency in individual action (Costa & McCrae, 1998). Even after the demise of grand theory, the concept of trait endured. Researchers elaborated a variety of trait models of personality. Depending upon the theory and the methods used in their extraction, the number of “traits” said to be constitutive of human personality varied from a mere handful to over 100. The trait approach was challenged with the rise of behaviorism in the mid-20 th century. Mischel’s famous (1968) critique of trait theories challenged the idea that one could identify