Since my retirement 10 years ago, Ape Mind, Old Mind, New Mind has been a work in progress. The basic ideas arose from my knowledge of the internal experience of the major mental illnesses directly imparted to me by thousands of my patients in 35 years of practicing psychiatry. The “data” of these composite descriptions are the foundation of the book and have not changed since I stopped practicing. What has changed are many discoveries in the field of paleoanthropology over this period of time. I have had a marvelous time integrating all of these findings into the book as they have come along. Of course, facts are king, and when the facts emerge, the book’s theories have had to “move over.” But even more important have been shifts in attitudes toward two of Darwin’s basic ideas. I had the advantage of reading Darwin’s treatises right at the beginning of my career, without knowing anything about the academic community’s attitudes toward them. I now believe that this has been a great advantage.
For example, I completely accepted Darwin’s theory of group selection that when groups compete with each other, natural selection favors cooperation within groups. Although I later learned that the academic community had discounted group selection, I continued to develop my own ideas about it, but, not having been formally trained in evolution, I lacked confidence in these ideas. So when E. O. Wilson (along with David Sloan Wilson) published a paper endorsing group selection in 2007, the year I retired, it gave me an injection of confidence that I was on the right track.
The second most important event occurred just as I was publishing the first version of this book about six months ago. The event was the publishing of Yale ornithologist, Richard Prum’s The Evolution of Beauty, in which he endorsed Darwin’s original conception of sexual selection, which I had also accepted since first reading about it over 40 years ago. When I read Dr. Prum’s book, the momentum to publish my book had taken on a life of its own and, although I hurriedly patched in comments about his work, I had not fully digested the impact of the authority of his endorsement on my thinking. After I read over the first version of my book I realized that my discussions of sexual selection were too tenuous. I decided that I had to rewrite it with the renewed confidence that Dr. Prum had imparted to me as to the importance of sexual selection in all aspects of human evolution. So these two important events occurred right at the beginning and at the end of writing this book. Although new science will continue to bubble up—most recently the explosion of paleogenetics—I don’t think anything as big as those two events are around the corner, but, who knows?