I shall address the concerns you raised in the 9 paragraphs of your comment.

1. To clarify the scope of my article: It is a criticism of one particular book. It is not an attempt to refute Christianity. Also, if, as you complain, “some of the quotes are fishy,” that is a problem with Lewis’ book, since he is the person I was quoting.

2. The problem of the fallibility of moral intuitions would express itself (in part) in questions like: How do you know that what you feel, believe, or reason is right actually is right? If you hear a voice commanding you, how do you know it’s God and not Satan? I don’t recall that this problem was addressed anywhere in Mere Christianity, at least not substantially, and it’s a major problem for Lewis’ argument. He appeals to each person’s recognition of “an influence or a command” (his words) within themselves. If the influence sometimes actually pushes us in the wrong direction, the Moral Law isn’t so Moral after all; or, if we sometimes misinterpret it, that calls into question our ability to recognize the Moral Law and thus to draw other conclusions about God and the afterlife. (The two sections of Lewis' book to which you alluded don’t address this topic. I believe you may have been confusing “moral fallibility” with “moral diversity.”)

3. You seem to be saying that I failed to observe, misunderstood, or did not engage a particular argument or “proof” of Lewis’. Since you didn’t identify exactly what I missed, I can’t agree or disagree about whether I missed it. Separately, to the extent that you say that my focus was too broad, as “not all of morality is needed for the proof” and Lewis doesn’t have to “teach all about” ethical philosophy, I disagree somewhat. An argument like Lewis’ does need to spring from a broader awareness of philosophy. He is sharing his understanding of how morality works, but he seems unfamiliar with the existing literature. He is entering a debate that is thousands of years old and he gives the impression of talking without having listened. Other philosophers’ accounts of how morality works are (in my view) more persuasive than his; due to my familiarity with them, I can spot obvious holes in his argument and I can think of better explanations than the one he is giving. He doesn’t say why he discards those other options.

4. OK, this is a valid criticism of my article. I wrote that Lewis “says” that the judgment between impulses is itself an impulse, and I did not cite an exact passage where he uses those exact words. My own sentence perplexes me today; I’m not sure exactly what I meant when I wrote it two years ago. (Although, if this is the only sentence in my 8,000-word article that is falling flat, then I don’t think my writing is overall quite as terrible as you make it out to be—but, yes, I am dissatisfied with this sentence of mine.) Probably there is not a sentence in Mere Christianity which outright says the Moral Law is an impulse because, if there were, I would have quoted it. Rather, I may have intended to gradually reveal how I drew this conclusion from Lewis’ words. Here’s how my thought process might have worked. (I am attempting to reconstruct it.) Lewis distinguishes the “instinct” or “impulse” to do a certain thing from the “influence” or “command” which judges between various impulses. He didn’t define his terms well, nor was I convinced by his distinction between those concepts. In my discussion, I suggested that "impulse" and "influence"—if we stare at them long enough—might collapse together. That is, they might turn out to be the same voice speaking, or part of the same dialogue between multiple input sources. Related to that: Lewis discusses his belief that God is simultaneously “outside” and “inside” us. He may intend to say that our personal “impulses” are “inside” us while God’s “influence” comes from “outside,” but he doesn’t maintain that distinction, because he also acknowledges that God speaks within us. Another possible theory: When someone believes they hear God’s voice inside themselves, they might be mistakenly identifying yet another of their personal impulses. Or, they are simply conscious of their impulses. Or, their impulses themselves gain consciousness, or impulse is identical with consciousness, or having impulses makes us conscious; the impulses have some “emergent property of consciousness” (to use language from another domain of philosophy). There does not need to be a Divine Person who is conscious of my impulses or who is causing me to be conscious of them. If there’s a way to know for sure what comes from my own impulses and what, by contrast, comes from some divine influence, Lewis needs to explain how to make the identification. Also, if the divine influence(s) might be God and/or angels and/or demons and/or Satan, it would be helpful to know how to pick the right one to listen to. (This is the best clarification I can give right now without rereading the book.)

5. Yes, I flagged this sentence of Lewis’ as a truism: “at those moments when we are most conscious of the Moral Law, it usually seems to be telling us to side with the weaker of the two impulses.” Beginning there, in the following three paragraphs I explained why I identify it as a truism. You seem to have misunderstood my point. I was not focusing solely on the phrase “the weaker of the two impulses”; I was not suggesting that we know what is moral based solely on whether it is hard to do. Importantly, I was simultaneously considering the first part of the sentence, which refers to “those moments when we are most conscious” of making a moral choice. Let me try again to explain: It is a truism that we are most conscious of making a moral choice when the choice is hard. By contrast, when we simply let our instincts lead us, we’re on autopilot, we aren’t spending energy arguing/rationalizing/practicing willpower, and we are less conscious that we are making a moral choice, by definition. Example: Two babysitters find alcohol in the house and choose not to drink it because it would interfere with their immediate childcare responsibilities. For one babysitter, who has never had an interest in alcohol nor a problem refusing it, the answer is so obvious and easy that it barely registers as a choice at all. For the other, an alcoholic in the early stages of recovery, not grabbing the bottle requires reason, emotion, and willpower. The second babysitter is more conscious of making a moral choice. Pretty much by definition. Since it’s a truism, it doesn’t help reveal—as Lewis intends it to—“that the Moral Law is not simply one of our instincts.” The fact that some choices (for some people, in some situations) are painful and require effort—along with the truism that we are more aware of whatever feels painful and challenging and less aware of whatever happens painlessly and unconsciously—does not demonstrate that there is a correct moral choice in that specific situation, much less does it reveal the nature of this moral information or the methods by which we can know it. (Which goes back to what I was saying in Item 4 above.)

6. It is important to call out racism in whatever context it occurs. Lewis wrote a chapter in which he claimed that Christianity makes people better even if it doesn’t make them perfect; he suggested that someone’s improvement ought to be judged on a personal basis and not in comparison with other people. His chosen example to illustrate this phenomenon was a weirdly racialized statement. So, are we supposed to take this seriously and are we supposed imagine that, were he not Christian, he would be saying something…more racist? That might be true. Maybe he would have been more racist without Jesus. No, I did not exactly express doubt that Christianity made him better or nicer; I simply said I “wonder” if it did. I was expressing curiosity, albeit with snark. Because, if he wants us to believe that his religion or religious philosophy has made him nicer, he is—in context and perhaps accidentally—inviting us to imagine him more weirdly racist. Ew. There’s not necessarily any problem with Christianity itself here, but there is a problem with the way Lewis wrote his book. Again, in this article, I am not refuting Christianity. I am making more modest claims about why this particular book is bad. Lewis easily could have picked a better (non-racist!) analogy. Instead, he chose a racist one...while threatening (implicitly, incidentally, accidentally) that he could have been more racist. Racist imagery in religion and philosophy is not a “totally insignificant” problem, and my complaint about it is neither “brainless” nor a “mudsling.” To the contrary, it is my ethical responsibility to point it out. When Black people read this paragraph, they may feel alienated (I’m not Black, but I’m guessing), and when churches recommend the book, they are putting another drop in their own bucket that tacitly shrugs at racialization and thus potentially leads to racial exclusion within their communities (and they could, if they wanted to, recommend other books that don’t risk causing this problem). The book’s decomposition into such nonsense toward the end reveals — and this is an additional type of problem — a deficit in Lewis’ writing/editing craft. Racist ideas are often poorly written; I and others have observed this, and it is another almost-truism in my belief system.

7. I do not believe in God. Therefore, I do not believe that confusing or paradoxical statements in the Bible must be reconciled. I am content to read the Bible as human literature. A poet’s metaphor might be interesting or beautiful to me even if it doesn’t accurately describe reality. I am fine with saying that certain theological statements—whether they derive from the Bible or from some more modern person’s imagination—are simply wrong. Questions like how God can “know everything, including the future, if he is within the timeline” (as you put it) simply suggest, to me and to many others, that the idea of omniscience might turn out to be self-contradictory because of time-travel paradoxes and other problems. These paradoxes and contradictions do not necessarily have any answers. Physicists and logicians have never resolved them. Lewis certainly doesn’t resolve them in Mere Christianity, which, in my opinion, does ramble. If someone were to resolve these questions for me, then I might revise my belief about whether God exists. Insofar as they remain unresolved, I can remain an atheist. From where I stand, it isn’t “necessary to keep the properties of God from contradicting himself” (as you put it). Many conceptions of God are self-contradictory, and I recognize that they are, and that's why I don't believe in God. It isn’t my job as an atheist to force someone else’s theology to make sense. If theists want to make better arguments, they are free to do so. But I have no interest in saying that one piece of apparent nonsense is useful because it coheres with another piece of apparent nonsense. That's not my project. Also: Lewis' goal in Mere Christianity, as I understood it, was primarily to make commonsense arguments in a folksy writing style—that is the sort of book that can sell hundreds of millions of copies and might deserve its status. But if the book also secretly requires readers to have background historical knowledge of theological arguments within the Church (and does not warn us of this or point us to where we can learn whatever it is that we don't know), the book isn't helping the reader, is it. The latter type of book belongs in academic obscurity.

8. No, I don't believe my own reasoning here is fallacious. “Fallacy” is a perfectly fine tag for this article. I am unpacking Lewis’ errors.

9. At the very beginning and again at the very end of my article, I said that I care more about the integrity of arguments than about popularity reflected in book sales. I have not tried to market a bestselling book because I do not value that activity. Repeating my observation about this is not a zinger.