I appreciate the latest of your eloquent and provocative comments. At this point it would be customary to congratulate the two of us for clarifying our disagreements. But I still get a queasy sense of not understanding exactly what we disagree about. Our worldviews seem so different that we are framing the questions in different ways.
You say that humans create and are influenced by cultural artifacts; I want to understand how and why our minds do so. You say we need to know something about John to understand John; I say we need to know something about the human mind, too. I say social science and biology should be connected; you say social science can never be reduced to biology. I try to explain some things in How the Mind Works; you say I don't explain everything. There needn't be any disagreements here, though you seem to be saying that there are.
I'm not sure what to make of "we who are human will resist all efforts to reduce our behavior to any one thing." Is my book trying to reduce behavior to one thing? (The book argues that the mind is composed of many complex systems.) And are those disinclined to resist this view not human? Inhuman? Subhuman?
Of course, dichotomies such as the natural vs. the cultural are ancient and still widely discussed, but that doesn't mean they are real or useful. Throughout history people have believed (and continue to believe) all kinds of kooky things.
A final comment: You say that if attempts to bridge biology and culture succeed, there would be no mysteries about us to explore. I am reminded of an observation by a former teacher, the great psychologist D.O. Hebb: Humanists believe that the world has a fixed number of mysteries, so that when one is solved, our sense of wonder is diminished. Scientists believe that the world has endless mysteries, so that when one is solved, there are always new ones to ponder.
I thank you for engaging the premises of the book so vigorously, and for stimulating thought in me and, I hope, in our readers.