Life is short. And there are much more pressing–and actually interesting–questions than “Are you less human than me?” — Ta-Nehisi Coates (@tanehisicoates) December 22, 2014

This is a striking way to frame the debate over IQ and race. And it genuinely grieves me that this is how Ta-Nehisi Coates views it. All I can say is that if I thought this was what this debate were about for a millisecond, I would completely agree. The absolutely equal humanity of every single soul on this planet is axiomatic to me. It is about as foundational an idea as I have ever held. It is the bedrock of any Christian faith, including mine. It is non-negotiable. As is the formal equality of all citizens, regardless of race or any other immutable characteristic. The idea that I was asserting the lesser humanity of a single human being, let alone a race, by airing a debate about race and IQ, is not how I saw it at all.

Now perhaps I should have. Perhaps the knowledge of the hurt that even airing these ideas would bring to many people would have persuaded me to try a different tack on the book. And if there had been an African-American staffer at the time, maybe the hurtfulness of this would have been brought much more powerfully home to me. I think on those counts, TNC has a strong case.

All I can say is that, for me, the debate about IQ and inequality wasn’t about that. Many debates in the past (and present) were; arguments about racial intelligence undoubtedly rang through the American centuries as a justification for pure evil, and still do. From the original sin of genocidal slavery to the eugenics of the Progressive Movement (championed by TNR in the 1920s!), these tropes undoubtedly contributed to monumental injustice and oppression. Was I tone-deaf with respect to this very dark and very American history as a young, English, Tory immigrant? I’m afraid I was. I’ve learned a lot since then, some of it because of Ta-Nehisi’s own work, which I championed from the moment I came upon it.

But an editor’s job is not, in my view, to suppress intellectual debate because of the social discomfort or even pain it might cause. So, for example, in Love Undetectable, I devoted a whole chapter to the literature and science of reparative therapy for homosexuals. It’s available here. Many readers found it deeply uncomfortable because I was much more sympathetic to some aspects of the argument – and even made a strong case for them – than is currently fashionable. The point is: I took the argument seriously, and, while criticizing large swathes of it, refused to dismiss it as mere “hate”. I even thought it had some real insights into the gay experience. Did this theory crush the souls and self-esteem of countless gay men over the last century? Absolutely. Was it the source of stereotypes and the argument that gay people were somehow just sick? You bet. Was it therefore all the more important to address head-on? That was my belief.

And the debate about race and IQ, for me, was never about someone’s humanity. It was and is about empirical evidence about a testable thing – IQ – that is one small sliver of what it is to be human, and a variety of competing explanations for it. The question was a relatively simple one: what can account for the clear differentials in IQ between the racial categories used by the US in its vast data sets?

Like many of Ta-Nehisi’s followers today, I assumed, before I had read the book, that all such evidence was made up, non-existent or peddled only by unreconstructed racists. I had had a good liberal education in which these subjects were simply never discussed. It was only by reading – and checking – the actual data in The Bell Curve that I discovered what my educators had withheld from me. These differences really do exist; they exist outside the black-white paradigm (for example, the resilient IQ differentials between Ashkenazi and Sephardic Jews); the bell curve for Asian-Americans is higher on the IQ level than whites; and these differences are not entirely dismissed by accounting for socio-economic class or culture. A huge amount can be attributed to environment. But not all – unless IQ was a trait unlike any other in human experience.

I was genuinely puzzled and fascinated by this; and still am. No one doubts that it is the case, and that it remains resilient. I really don’t understand why liberals are not engaged on this. The explanations for it might be utterly different than assertions about genetics. Here, for example, is Freddie DeBoer, actually addressing the undisputed data, and making just such an argument from the left:

These differing outcomes are the result of massive and entrenched disadvantages that reflect this country’s legacy of hideous racism and its ongoing, massive racial inequality in economic and sociological factors that impact quality of life. Often, race science types will say that a particular piece of research “controlled for poverty.” But such controls are typically limited to income level or parent’s wealth. Because racism is such a pervasive and all-encompassing phenomenon, these controls are never remotely adequate. In order to really assess these differences, I’d have to feel comfortable accounting for cultural biases in the nature of the questions, parent’s income, parent’s wealth, parent’s level of education, family stability, exposure to crime, exposure to drug abuse and alcoholism, the psychological and social impact of explicit and implicit racism, the Matthew Effect ... Take exposure to lead. We know that black children have significantly higher exposure to lead than white children even after controlling for poverty level. This is what I mean when I say that saying “we controlled for social class” is so inadequate.

So for Freddie, the data underlines his racial progressivism. It’s proof of the very “white supremacy” that TNC believes defines modern America. The data, in other words, can cut in many different ways.

And at some point, we’re going to have to grapple more honestly with it. It’s a huge challenge for a liberal technocratic society that the skills it increasingly rewards are unevenly distributed across racial groups. It’s equally a huge challenge for our society that the kind of intelligence IQ measures is so strongly correlated with economic success, regardless of race, and that the rewards to the most gifted in these areas are growing, not shrinking. The Bell Curve was one of the great prophetic books of our current crisis of inequality. It raised very troubling questions about this country’s ability to advance economically and not stratify into two, increasingly separate and mutually uncomprehending nations. And yet the important thing to say about it, according to so many who have never read it, is that it should never have been published and no one should have responded to it.

Where do I stand on the core question of what lies behind these intractable differences in bell curve distributions? I don’t know. I feel pretty confident that a huge amount of it can be ascribed to the kinds of factors Freddie cites. My deepest objection is to the very concept of “race” as we measure it. It’s far too crude and too vague a term to be of much use as an empirical matter. But am I convinced that genetics has nothing whatsoever to do with IQ? Sadly no. Genetics have a role in explaining all human activity and experience. It would be bizarre if IQ were the only exception to this general rule.

One small remaining factual point. Ta-Nehisi on Twitter keeps asserting that The Bell Curve argued that all African-Americans are somehow subhuman or intellectually inferior to all white Americans, when it did absolutely nothing of the kind. What the very title of the book refers to is a distribution curve, which proves that on the limited measure of IQ, many many African-Americans have far higher IQs than many, many whites, but that the bell curve peaks at a higher level for whites and even higher for Ashkenazi Jews and Asians. The book is also clear that the overlaps between all racial groups are far more striking than the gaps. More to the point, it insists – and did so repeatedly in the excerpt – that no moral quality can be attached to such a culturally specific measurement as IQ. So much of TNC’s rhetoric against this book is not actually about the book at all. He is debating imaginary arguments in his head because he refuses to debate the actual ones in the data.

What, to paraphrase Freddie, is he afraid of? And what happens when liberalism chooses not to challenge its own shibboleths, not to debate certain troubling ideas, not to explore forbidden fields of inquiry? It becomes a tired and tiresome orthodoxy – like much of modern conservatism – preferring feelings over facts, and solidarity over reason.

So yes, I will miss TNR. For all the reasons so many on the current, homogeneous, identity politics left will not.