If you take this book literally you have completely missed the point. Moreover, you've failed to notice the date of publication. As a Psychology major, and current marketing and promotional analyst, for as absurd as some of this text is, it is just as logical as any other ways we have to describe human behavior. When genetics plays such a large role in determining preferences toward activities, mates, and talents, one would be foolish to ignore the biology between these differences. In all my schooling, research, and personal experiences I have found many, many, more absurd techniques for understanding humans than this. I will say rather than view this book as non-fiction assumptive science, view it as fiction. View it as a suggestion as to why we settle into the roles in life that we do, and consider the very under-represented role biology plays in it.