In the Social Sciences capstone at Shimer, we spend a lot of time on texts that emphasize the social mediation of reality and call into question any kind of simplistic empiricism — Mannheim’s “sociology of knowledge,” Foucauldian power analysis, feminist critiques of the scientific enterprise, etc. One thing that has stood out to me in these readings is how often they are haunted by the specter of relativism. Mannheim probably does the best job of accounting for the problem out of our readings, pointing out that it is a kind of intellectual halfway house where the idea of absolute truth has been denied and yet the basic dichotomy of absolute truth vs. opinion has persisted — hence if nothing (alas!) can attain to the impossible ideal of absolute truth, everything must be “your opinion, man.”
Other readings are more openly scornful of the idea of relativism, though the attention they give to it shows that they expect it to be tempting. And in my experience, it is tempting for a population I spend a lot of time with: undergraduates. One might even call relativism the spontaneous ideology of the first-year college student. The absolute truths of their upbringing are being called into question. Even if they are able to dispense with the content of their previous truth, though, it will take time and work to get rid of its form — hence the ideal of unlimited open-mindedness and the profound realization that “everything’s subjective.”
It may not work well as a consistent intellectual position — though once in a while you’ll get the truly principled relativist who’s unwilling to pass judgment even on Nazis or slave traders — but it does function as a strategy for avoiding conflict. If the negative reference to relativism is a kind of trump card in high-flown theoretical debates, it serves as a different kind of trump card in the student lounge: any serious argument can be shut down before it gets too heated. At the same time, it serves as a means of self-defense as well, because if one’s views are worthy of respect simply by virtue of existing, one does not have to put in much work in defending them (to others or oneself).
I know it sounds like I’m making fun, and to a certain extent I am. But I don’t think we should underestimate the extent to which this somewhat irritating step in the process is necessary — not only on the world-historical level charted by Mannheim, but in the unfolding of the individual mind. Eventually one starts to realize that total relativism simply isn’t very interesting and that it doesn’t make sense to say that the best way to “respect” intellectual positions is to abstain from seriously engaging with them. Even if the quest for absolute truth is fruitless, there is still local knowledge to be had, and perhaps that local knowledge will turn out to be richer and more interesting than the illusion of absolute truth ever could have been. Even the self-defensive move of exempting one’s own views from criticism is shifted into a more productive gear, as one becomes capable of detaching oneself from one’s opinions and assessing them critically — indeed, one might perhaps learn that the having of opinions is not an end in itself and that engaging in the search for local knowledges can be more satisfying without the teleology of the “hot take.”
To get to that point, though, one needs that initial act of purely negative suspension.
An und für sich 
One should read Gramsci on this. Excellently brought by Peter Thomas: http://books.google.co.uk/books/about/The_Gramscian_Moment.html?id=Kc5f3Ybv6xMC
I wonder what this spells for students who, like myself, never underwent a relativist phase.
In Mannheim’s terms, it would mean you’re either hopelessly behind the times or the vanguard of the future.
I’ll go with the former.
It’s worth noting, by the way, that the ideology is not always wholly the product of unprompted spontaneity on the part of undergraduates. At Shimer, at least, “cultural relativism” seemed to be the official creed of Ruth Benedict in *Patterns of Culture*, which is assigned very early on in the Social Sciences sequence.
No such sentiments appear in the Hum 1 readings, however, and I often learn from students in that class that “art is subjective.” Indeed, any arguments I advance to the contrary often seem to have no effect whatsoever.
Having spent a lot of time teaching first year students in something akin to a Shimer classroom—what we call a “first year seminar” (where seminar is defined as less than 35 students)—I think your analysis is more or less correct. They like to say their “opinions” and what “they really believe,” but when pressed for the grounds of this opinion or belief, they have nothing more to say than “it’s natural.” Some idea of “nature” (or, perhaps, “Nature”) is a regulative idea for them. But, ask them what makes nature natural… they’ll come up with some opinion or something that is deeply social. Basically, I guess, the first thing humanities and social sciences undergrads should read is Latour’s We Have Never Been Modern. (But then you’d have to explain why people came to fisticuffs over an air pump—”What’s that?”)