Ideas, like individuals and nations, have histories, and so do the research enterprises that sometimes stem from ideas. The his- tory of the research that is reported in the following pages is mainly one of indebtedness. The ideas out of which it grew have a remote ancestry in those of Charles H. Cooley and George H. Mead, and an intermediate one in some things I learned from my own research at Bennington College twenty years ago. Their more immediate ancestry can readily be traced to my former col- league, Professor Leon Festinger, and to the writings of Professor Fritz Heider. And from Dr. James G. Miller and his associates I have learned some of the advantages of treating these borrowed ideas in system-like terms.