Thomas Sutcliffe: Audiences can be infectious

According to one witness, when Oscar Wilde addressed the audience after the successful opening night of Lady Windermere's Fan he graciously complimented them on the "great success" of their performance. Another witness, an American journalist, disappointingly gave a far drabber account of the playwright's curtain speech, one in which he said nothing of the sort, but I think we can agree to ignore her unhelpful contribution to the historical record. Secondary vanity, on behalf of Wilde's reputation as an aphorist, and direct vanity – on behalf of our own significance in the theatre – means that the first version is far more likely to survive. We like the idea that we're collaborators in the theatrical moment, rather then mere passive consumers, and Wilde's quip (genuine or not) seems to acknowledge a creative connection. It feeds directly into the pleasure we take in those moments when our presence in a theatre is suddenly conspicuous; which is another way of saying when we stop thinking of ourselves as "I" and are suddenly obliged to pay attention to "us".

This isn't by any means a given when you go to the theatre. Of course you know that everybody else is there – and there will be times when you're aware that you share a response in common, most obviously when the audience laughs at something. But laughter is a slightly compromised example, since there are quite a lot of occasions when an audience laughs simply because one person has and everyone else feels they'd better go along with it. They – or we – aren't exactly being dishonest when we do this, we're just going with the flow (sometimes in the hope that by laughing a play will be rendered funny), and often it's only later that we wonder whether anything really was funny.

More interesting, though, are those moments when an audience takes a collective intake of breath, and not because of some trapdoor plot surprise but because of something that has been uttered. I went to a play in which it happened a couple of times last week, and it counted as a kind of saving grace in the evening.

The play was Happy Now, Lucinda Coxon's entertaining black comedy at the Cottesloe, and the biggest gasp was elicited by a scene in which one of the characters, a primary-school teacher, discovers that his friends have just taken their daughter out of his state school to put her into a private church school. Railing at their betrayal and unplacated by their justifications (she's "gifted" and wasn't being "stretched"), he walks out of the dinner party with one parting blow: "Your child," he declares loudly, "is NOT gifted." And almost as one the audience gave an audible wince at the enormity of this offence against polite fictions.

A friend at the same performance dismissed Happy Now as "superior sitcom", which seemed unfairly harsh to me, even if some scenes are a little sketch-like. And defending the play, that gasp was one of the things I called in evidence. A line works very differently, I argued, when you experience it in concert with others and have to think about what your collective response really means. The choral nature of the response isn't, after all, inherently virtuous (even if the more pious proponents of theatre sometimes seem to argue that). A mutual gasp might be an expression of complacency or unexamined prejudice, as much as evidence that the writer has found an intriguing pressure point in the collective consciousness. But at least you find yourself thinking about it in the theatre, and wondering what it is that governs the identity of your response.

The fact that the answer to this can sometimes be nuanced and problematic had been brought home to me a couple of weeks earlier at a performance by the American stand-up Chris Rock. As expected there were plenty of collective gasps in that, too (the phrase "Yeah... I said it" isn't one of his catchphrases for nothing), but very few of them united the audience in any simple way. Much of his material on race, for example, presupposed a shared experience that just isn't true of a mixed London audience. The jokes weren't divisive per se, but a slight and necessary self-consciousness about what it was to laugh at them as a white or a black person was.

A little later Rock sliced the audience into different divisions, between those who would fret over potential misogyny and those who were unperturbed. A little after that we were invited to think about sexual difference, too. When they eventually get round to releasing the DVD of his British tour I don't suppose a joke will be missing. But the audience will, and with it a critical bit of the evening.