In the fall of 1966, my then wife, Carol, and I entered graduate school at the University of Chicago, in the Department of Psychology. Carol was studying Developmental Psychology with Lawrence Kohlberg, and I was to study Comparative and Physiological Psychology with Sebastian Grossman (that relationship didn’t work out, so I ended up with George Stevens as my advisor). One of my courses was Ethology, taught by Eckhard Hess. Hess had arranged for one of Konrad Lorenz’s students, Wolfgang Wickler, to come to the University of Chicago to speak about his work with dominance hierarchies and aggression with monkeys (described in the second section of this document).
Wickler’s presentation was fascinating, revealing previously unknown (to us, at least) relationships between sexual and aggressive behaviors. Most telling, though, was his adherence to ethological canon, that sex and aggression emanated from separate motivational drives, but ended up conjoined through the course of evolution in the establishment of dominance hierarchies. One of Wickler’s conclusions was that sexual behavior in the service of aggression was “pseudo-sexual,” to be distinguished from “true sexual” behavior. However, it was not clear how an observer would be able to tell the difference between the two, other than by noting the genders of the individuals and the outcome of the interaction.
At some point in our discussion on our way home from the lecture, Carol asked the crucial questions that stimulated and guided our own studies of sex and aggression over the next several years: “What if there really isn’t any difference between “pseudo-sexual” and “true sexual” behavior? What if, for the animals involved, they are the same? ”
We spent the entire night working with those questions, hypothesizing different mechanisms that would explain Wickler’s findings, but rejecting the two-drive approach. We managed to formulate the basic principle of the theory we present in the third section of this document, but it took several years to develop fully and get our thoughts on paper.
We completed “An Evolutionary Theory of Social Interaction” in 1970, and printed a hundred or so copies using an old mimeograph machine. The stencils were not very good, and many pages were dim and almost unreadable. Nonetheless, we sent two copies to the Library of Congress along with our filing for copyright. I always intended to expand these ideas into a book, along with examples of behavior in different species that confirm our hypotheses, but life interfered. So 48 years later, I retyped the manuscript, edited some glaring grammatical errors (most notably, which-that substitutions), and added some footnotes and a new graphic.
As you read this document, please remember that it was written in the late ‘60s. Since then, there has been a significant amount of research and conjecture on the relationship between sex and aggression, but to my knowledge, no one has come up with the theory that we present here.
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