An excerpt from the final installment:
On the question of morality, you again attempt an answer: "My answer is the same as it was all along: Our morality evolved." There are two points to be made about this reply. The first concerns evolved morality and the future, and is a variation on my previous questions. If our morality evolved, then that means our morality changes. If evolution isn't done yet (and why should it be?), then that means our morality is involved in this on-going flux as well. And that means that everything we consider to be "moral" is really up for grabs. Our "vague yet grand conception of human rights" might flat disappear just like our gills did.
Our current "morals" are therefore just a way station on the road. No sense getting really attached to them, right? When I am traveling, I don't get attached to motel rooms. I don't weep when I have to part from them. So, in the future, after every ferocious moral denunciation you choose to offer your reading public, you really need to add something like, "But this is just a provisional judgment. Our perspective may evolve to an entirely different one some years hence," or "Provisional opinions only. Morality changes over time"—POOMCOT for short. It would look like this: "The Rev. Snoutworthy is an odious little toad, not to mention a waste of skin, and his proposal that we prosecute the brassiere editors of the Sears catalog on pornography and racketeering charges is an outrage against civilized humanity. But … POOMCOT."
This relates to the second point, which concerns evolved morality and the past. When dealing with people whose moral judgments have differed from yours, do you regard them as "immoral" or as "less evolved?" The rhetoric of your book, your tone in these exchanges, and your recent dancing on the grave of the late Jerry Falwell would all seem to indicate the former. In your choice of words, the people you denounce are to be blamed. The word fulminations comes to mind. You write like a witty but acerbic tenth-century archbishop with a bad case of the gout. But this is truly an odd thing to do if "morality" is a simple derivative of evolution. Are you filled with fierce indignation that the koala bear hasn't evolved ears that stick flat to the side of his head like they are supposed to? Are you wroth over the fact that clams don't have legs yet? When you notice that the bears at the zoo continue to suck on their paws, do you stop to remonstrate with them?
Your notion of morality, and the evolution it rode in on, can only concern itself with what is. But morality as Christians understand it, and the kind you surreptitiously draw upon, is concerned with ought. David Hume showed us that we cannot successfully derive ought from is. Have you discovered the error in his reasoning? It is clear from how you defend your ideas of "morality" that you have not done so. You are a gifted writer, and you have a flair for polemical voltage. But strip it all away, and what do you have underneath? You believe yourself to live in a universe where there is no such thing as any fixed ought or ought not. But God has gifted you with a remarkable ability to denounce what ought not to be. And so, because you reject him, you have great sermons but no way of ever coming up with a text. When people start to notice the absence of texts, the absence of warrant, the absence of reasons, you adjust and compensate with rhetorical embellishment and empurpled prose. You are like the minister in the story who wrote in the margin of his notes, "Argument weak. Shout here."Check out the whole debate here.