But he also appears to have a new argument to sell. Leiter advocates a new way to divide the philosophical canon, not into "contintentals" or "analytics," but rather into "naturalists" and "anti-naturalists". You can also listen to Leiter's argument on the latest Philosophy Bites episode, where Nigel Warburton thankfully pushed back a bit.
It seems to me that Leiter focuses too much on outlier examples to deny the boundaries of the "continental" and "analytic" camps. Sure, perhaps Marx wouldn't have thought much of Derrida (though who can say, and what kind of an argument is that, really?). But that doesn't mean they weren't both united as students of Hegel, and therefore assignable to a certain intellectual camp. I mean, Heidegger didn't think much of Sartre, either, but that doesn't mean they weren't more similar than different when compared to Frege and Russell. Not all Republicans agree on all points with their fellow Republicans, but they can still sense when a Democrat has entered the room; there's a reason these camps evolved in the first place.
And perhaps the discourse of analytic philosophers can also be criticized as impenetrable, just as so-called "continental" philosophers are accused of using obscurantist language. But that's not the same phenomenon at work. As Warburton pointed out, logical language and technical jargon is often required to maintain an argument within the analytic tradition. And such language is certainly clear within that group, in the same way that mathematicians converse in a clear and readily understandable language amongst themselves. Anyway, Leiter's description of the language of analytic philosophy is only apt when describing analytic philosophy journals, where these professionals are only talking to each other, and not to the public at large. So of course professional jargon would predominate; a lay audience reading a medical journal would also become overwhelmed by the medical jargon. But that doesn't prove that the language of analytical philosophers isn't more rigorous than, say, Lacan or Deleuze.
I agree with Leiter that these kinds of Venn diagrams have limited utility. But for Leiter to suggest that the traditional distinctions have naught but "sociological value", whereas only his championed categories have genuine explanatory value, strikes me as unpersuasive. I'm sure Leiter's naturalist/anti-naturalist categories have explanatory value, yes, but only in that they organize these thinkers according to criteria which Leiter himself deems important. If you look at any set of cars in a parking lot, you can organize them by color, engine size, chassis, country of manufacture, etc. Any particular categorization might be useful, depending upon what you were trying to accomplish with your grouping. His proposed criteria may catch on, or they may not, but that he must take the time to even argue for them bodes ill for their future adoption, and indeed their utility. I think the real "sociological" insight of these categories is not why people go with "continental/analytic" for their distinctions, but why any such divisions, including Leiter's, are made at all. The history seems clear that the "analytic/continental" divide was first created (if not explicitly named) by the post-Russell logical positivists, who wanted to separate those they would take seriously from those they wouldn't. In that sense, it served, and to a similar degree still serves, a useful function.
Finally, adopting new philosophical definitions using the word root "natural-" seems to me unhelpful, as earlier definitions already appear to have been claimed for terms like "naturalism" or "naturalists," even as alternatives to "analytic"/"continental". Exercising "eminent domain" over the existing nomenclature will lead to more confusion, not less.
Unlearned and unearned quibbles aside, Leiter's forceful approach makes him a great interview, so check it out:
There are real dividing lines in the history of philosophy, but the one between the “analytic” and the “Continental” isn’t one of them, though it’s interesting today from a sociological point of view, since it allows graduate programs in philosophy to define spheres of permissible ignorance for their students. A real dividing line, by contrast, one that matters for substantive philosophical questions, is between “naturalists” and “anti-naturalists.” The naturalists, very roughly, are those who think human beings are just certain kinds of animals, that one understands these animals through the same empirical methods one uses to understand other animals, and that philosophy has no proprietary methods for figuring out what there is, what we know, and, in particular, what humans are like. The anti-naturalists, by contrast, are (again, roughly) those who think human beings are different not just in degree but in kind from the other animals, and that this difference demands certain proprietary philosophical methods - perhaps a priori knowledge or philosophical ways of exploring the distinctively “normative” realm in which humans live.
So on the naturalist side you get, more or less, David Hume, Ludwig Feuerbach, Karl Marx, Ludwig Büchner, Friedrich Nietzsche, Rudolf Carnap, W.V.O. Quine, Jerry Fodor, Stephen Stich, and Alex Rosenberg and on the anti-naturalist side you get, more or less, Gottfried Leibniz, Immanuel Kant, G.W.F. Hegel, Edmund Husserl, Gottlob Frege, Jean-Paul Sartre, G.E.M. Anscombe, Wilfrid Sellars (at least for part of his career), the older Hilary Putnam, Alvin Plantinga, and John McDowell, among many others. This disagreement - a disagreement, very roughly, about the relationship of philosophy to the sciences - isn’t one that tracks the alleged analytic/Continental distinction. Indeed, the founders of the 20th-century traditions of “analytic” and “Continental” philosophy (Frege and Husserl, respectively) are both on the anti-naturalist side, and both are reacting against hardcore naturalist positions in philosophy that had become dominant on the European Continent in the late 19th-century. And the first explosion of what anti-naturalists would derisively call “scientism” came in Germany in the 1840s and 1850s, as a reaction to Hegel’s obscurantist idealism. Naturalism and anti-naturalism mark a profound dividing line in modern philosophy, but it has nothing to do with “analytic” vs. “Continental’ philosophy....