The first thing about them is, they would have you believe that yes, things really do matter to them, more so than they ever could to a poor sot like you. The proof of it is this, that they heard about it first. The nature of their challenge is this, not that it maligns our taste or judgment, but that it threatens to steal our experience, or vandalizes the place that experience holds in our memory.
We say, "The other day I picked up a photography book by so-and-so, and there was one profile portrait that reminded me of. . ."
"Oh, so-and-so," the Primus Auditor break in. "Yes, I believe I remember them from an opening six months ago, maybe a year, I can't really remember. What did you think of the black and white nudes?"
But by the time he asks, even the thought of black and white nudes cannot reconcile you to an even temper. You can forget that you were interrupted; at parties of eight or more that sort of thing ceases to be a breach of chivalry. You are angry because he stole your subject line before you could effectively delve into your topic of choice. He might as well have sampled your dessert before you had a chance to do so.
Now the collective subconcious of the other listeners (if you are a man who finds himself being humiliated, these will most likely be female) is of course keeping track of the movements of conversation and who most forceably directs them. This commitee of umpires awards points for the introduction of subjects (anything north of moderately dull will suffice) and subtracts them for defensive responses to the other man (if you are a man, so will your opponent be), regardless of how sensible or clever these are. Always remember, if your audience is female, it matters less what you say than that you say it first.
If, as in the example above, the other man steals your point of discussion before you can share your opinions on it, you can always alter those opinions for tactical advantage, so that you look as though you belong to some Higher College of Illuminati and the other man looks like an ass.
If he says he saw so and so's work at an opening while you only saw it in a coffee table book, then turn this around on the bastard. Say something like, "Oh you did? I hope you didn't make a bid on anything, chief. He's so maudlin and foggy, after all. Might as well save yourself the money and buy an Ansel Adams knockoff down at the nearsest print shop." I promise you, the advantage will be in your favor, and the ball in his court. Be ready though, lest he recover himself.
To recover from the above verbal blitzkrieg is usually favored only to the Truly Confident Tool. That he is a Tool you had already decided, but that he has the footwork to dodge your fusilade you had not foreseen. Suppose he were to escalate the encounter from skirmish to frontal assault? "I can't believe you thought that. Obviously you didn't read the exclusive in New York Times Magazine/New Yorker/Men's Vogue. It's clear that his work doesn't have even the slightest hint of sentimentality in it. 'Deliberately confrontational' was what the reviewer's notice said." Check the article out if you like."
If the article was in Men's Vogue, and this metro not only read it, but admitted it in public, then he has dismembered himself better than you ever could have, unless you are the second coming of Jonathan Swift. Here I advise you to give a knowing half-smile to one of the ladies present, preferably one of the prettier ones, finish your whisky sour, say you're going to get another drink and vanish. On second thoughts, offer to get the lady another while you're away. Then when you leave, pat the other guy fraternally on the shoulder, as though none of this really mattered to you and it was all just another exchange between two gentlemen, neither looking to vantage himself above the other. If one shot himself in the foot by reading a magazine that smells like Rufus Wainwright's nightgown, then you have our sympathies, brother.
But let us be realistic. The article is probably not in Men's Vogue, or if it is, he will probably say it was Esquire. The point is not to panic, even if you haven't read the exlusive interview with an up and coming Soho portrait photographer, which, if you are a man at all, is most definitely the case.
So why not condescend to the jackass? Something like, "No, I'm not really up on any of that guff. Guess I'll just have to take your word for it. Which magazine was it again?" Whenever you get the chance, make him repeat things. It leaves him thinking that maybe his voice lacks amplitude or resolve, or both, or that what he's saying isn't important enough to register with you. Either way, you'll get to him. Once you play the, "Your opinion, or an opinion you bought at some dingy newstand isn't important enough for me to give a damn for" card, he'll either offer you more proofs to the contrary (i.e., more references to articles nobody cares about) or he'll leave you with the last word and go sulking off. Then you can get around to the girl, and the second whisky sour.
And remember, you heard it here first.