Christianity is, from the outside, a “strong misreading” of Judaism (and, from the inside, it’s Judaism that is a weak misreading of Israelite religion); Islam looks, from the outside, rather like an imitation of Judaism (and, from the inside, it’s Judaism which is a degenerate form of Islam). From a Christian perspective, what Ross says – that the common scripture creates more fruitful grounds for dialogue between Christians and Jews than between Muslims and Jews – might seem sensible. But from a Jewish perspective, I’m not sure that’s the case. It’s arguably easier to dialogue with someone who’s reading a different book in the same way than with someone who’s reading the same book in a very different (and incompatible) way. Another way to put it: Christians need to have a relationship of some kind with Judaism (if not with Jews), but Muslims basically don’t. But why should that make relations between Christians and Jews (or between Christianity and Judaism, if you prefer) more fruitful as opposed to more fraught? After all, Judaism doesn’t need a relationship with Christianity. How do lopsided relationships like that usually work out?
I agree with Ross that the term, “Judeo-Christian” is a way of “baptizing” Jews into America’s overwhelmingly Christian culture – and that’s exactly why I don’t like it. I also don’t like it because I suspect it’s a way of kashering an intellectual attempt to Christianize the Enlightenment. To argue that modern liberal democracy is an outgrowth of Christianity – and is ultimately parasitic on a living Christian community – well, that might be taken more amiss than to argue that it’s an outgrowth of “Judeo-Christian” tradition, whatever that is.
But Razib’s assertion that Judaism was, for most of its history “not part of Western civilization” is, I think, inadequate. If there is an Indian civilization, the Parsis are part of it, are they not? The only way to take the Jews of Europe out of the story of Western civilization is by limiting yourself to the times and places where the Jewish community was numerically insignificant – that is to say, in Ashkenaz in the Dark Ages.
Moreover, what is this “Western Civilization” of which you speak as if it were an unbroken chain from Athens to Los Angeles? One of the peculiarities of Western civilization (as against, for example, Chinese civilization – that’s my impression, anyway) is the extreme porousness of its boundaries. Western civilization famously has its roots in Athens and Jerusalem, but Western civilization also has roots among the Germanic barbarians of the north, from whence we get many of our major languages and cherished political traditions (trial by jury, for example). And modern Western civilization as it actually exists has some substantial Jewish roots (Freud, Kafka, Einstein, Rothschild, all that). And Judaism as it actually exists in the West is the product of the Enlightenment – even Orthodoxy as it actually exists is such a product, unavoidably so. The ultra-Orthodox world may be so predominantly as a reaction (much like fundamentalist religious movements outside the West), but modern Orthodoxy is a very self-conscious attempt to recast traditional Judaism in terms that would make sense in a Western philosophical context. I don’t think that there is any actual tradition to provide content to the term “Judeo-Christian tradition” – but you could well make the argument that the West as it exists is a “Judeo-Christian civilization” simply because the scale of Jewish contributions to that civilization ought to be recognized (rather as the scale of African contributions ought to be recognized when we talk about the character of American civilization).
To some extent, the same can be said of the Islamic world – but only to some extent. If Goitein is right (and I’m in no position to dispute with giants like him), mature (that is to say, medieval) Rabbinic Judaism owes as much to Islam as classical Islam owes to early Rabbinic Judaism. (Note, for example, that while the Talmud plainly is a record of argument about arguments – Amora’im elaborating on the debates of the Tanna’im – far removed from Mosaic times, it is treated by the tradition as if it were something akin to the hadith – a record that ultimately traces itself back to sayings of the founding prophet of the faith.) But I’m not sure that after the period of earliest origins Islam took all that much from Judaism. Nor was there any theological reason for it to pay Judaism any mind until the emergence of Zionism forced the question. So the idea of a “Judeo-Islamic” tradition or civilization is rather a stretch.
If the goal is to do a taxonomy, you could group Jews and Christians together as common descendants of Israelite religion; you could group Jews, Muslims and classical Unitarians together as strict monotheists; you could group Jews, Hindus and Confucians together as ethno-religious systems; you could group Jews and Parsis together as oddball religious minorities . . . Each of those divisions makes sense for a specific purpose. The purpose of asserting a “Judeo-Christian” tradition, being political, probably suggests limited utility for analytical purposes.