I came across
this quote today, in the context of a book review of Judith Harris's new book, No Two Alike: Judith Harris .. has attempted to formulate a new theory of personality formation - the first, in fact, since Sigmund Freud. Basically, Mrs. Harris believes there are three "perpetrators" at work in the formation of the human personality, each associated with an aspect of a modular brain. One is the "Relationship System," designed to maintain favorable relationships in society. Another is the "Socialization System," where the goal is to be a member of a group. The third is the "Status System," where we compete with our peers for status. The interplay among these systems accounts for the emergence of differences between individuals.
No offense to Mrs. Harris, but this thesis has been a core assumption on the formation of personality in much of Singularity fiction: see the opening chapter of Greg Egan's Disapora to see it described. It is an underlying assumption of Minsky's "Society of Mind" thesis. It has been explicitly described in several texts on Evolutionary Psychology (most notably Non-Zero by Robert Wright). It's a defining feature of and discussed in several episodes of The Journal Entries where the tension between anarchy and chaos play out in the tensions of "wanting to get along" while "wanting to get ahead". As I've said in a couple of places, most human progress arises from creative responses to that tension.
Even worse, it's incomplete. Mrs. Harris completely misses out on a fourth system, one that is as important as the others and completely necessary to understanding certain aspects of personality: The Other System. "Other" as in "Reacting to those who are neither family or peers." How we identify ourselves and our peers by what they are not: not a different color, not a different gender, not a different religion, not a different language, and so on. Unless and until Mrs. Harris or those who follow her deal with that aspect of development, any theory of personality will be incomplete.
Fortunately or unfortunately for Mrs. Harris and reviewer Peter Pettus, science fiction writers are a decade ahead of them.