like language generally, is a key to both the maintenance of their separate identity and the fulfillment of their commercial (conjoining) function. Once again, however, difference is primary. The continued fulfillment of their conjoining function (like all acts of mediating, negotiating, and translating) hinges on the perpetuation of difference, and difference makes for strange bedfellows: wherever Mercurians live, their relations with their clients are those of mutual hostility, suspicion, and contempt. Even in India, where the entire society consists of endogamous, economically specialized, pollution-fearing strangers, the Parsis tend to feel, and may be made to feel, stranger and cleaner than most. 27 Elsewhere, there was little doubt about a mutual antipathy based ultimately on the fear of pollution. “They” always eat filth, smell funny, live in squalor, breed like rabbits, and otherwise mix the pure and the impure so as to contaminate themselves beyond redemption (and thus become the object of intense sexual curiosity). All contact with them, especially through food (hospitality) and blood (marriage), is dangerous, and therefore forbidden—and therefore desirable. And therefore forbidden. Such fears are rarely symmetrical: border crossers are always interlopers and outcasts and thus more contagious, more difficult to contain and domesticate. In complex societies with well- established universalist religions the nature of the relationship may change: the border crossers retain their preoccupation with everyday pollution and intermarriage ( shiksa means “filthy”), and the host majorities profess to fear certain religious practices and political conspiracies. Still, much of the anti- Mercurian rhetoric has to do with contagion/infestation and, in cases of particular resonance, specifically with food and blood: casting spells to destroy the harvest, using the blood of infants to prepare ritual meals, and jeopardizing Christian Spain’s limpieza de sangre (“blood purity”)—in addition to basic untidiness. The asymmetry goes much further, of course. The host societies have numbers, weapons, and warrior values, and sometimes the state, on their side. Economically, too, they are generally self-sufficient—not as comfortably as Ferdinand and Isabella of Spain may have believed, but incomparably more so than the service nomads, who are fully dependent on their customers for survival. Finally, beyond the basic fear of pollution, the actual views that the two parties hold of each other are very different. In fact, they tend to be complementary, mutually reinforcing opposites making up the totality of the universe: insider-outsider, settled-nomadic, body-mind, masculine-feminine, steady-mercurial. Over time, the relative value of particular elements may change, but the oppositions themselves tend to remain the same (Hermes