I lose track of the number of invitations I receive to discuss "the death of the critic". The subject came up again last weekend, at a conference in Stratford-on-Avon entitled Reviewing Shakespearean Theatre: the State of the Art. I gave a talk which conceded that criticism, like Shakespearean production, is in a state of flux. Professor Peter Holland flew in from the University of Notre Dame in the US to tease both newspaper critics and bloggers for being confined to their own little bubbles. In a stimulating seminar session, Elle Collins argued that criticism should echo the collaborative nature of theatre: instead of a closed text, there should be a "dialogic confrontation" in the blogosphere.

Only a fool would deny that criticism has been affected by the rise of new technology. But I've spent my life arguing that a review is simply a way of starting a debate. I also think it's time to bury the myth that in the past critics were unaccountable, god-like figures. Criticism has always triggered meaty public debates. Years ago, I observed that we should have a UK Shaw festival, since he was our second-best dramatist after Shakespeare. The result was a blistering attack from John Osborne and a correspondence that raged, on our letters page, for weeks rather than days.

What has changed is the technology: any opinion is now open to instant, rapid rebuttal online. Sometimes this leads to fascinating discussions: this year, my own hesitant suggestion that there was a potential danger in theatre adopting the cinematic model of the "auteur" unleashed a host of contradictory opinions from readers. But it seems to me absurd to deduce from this that printed criticism is dead, dying or redundant. In any sphere of activity – be it politics, sport or fashion – there is a crying need for someone who brings to the subject a lifelong professional commitment: more than ever, I'd argue, in an age of spin and hype. You can attack particular critics – and it has been known to happen – as being out-of-touch or past their sell-by date. But I came away from the Stratford conference convinced that we still need critics, not least because they provide, in the excellent words of Shakespeare professor Carol Chillington Rutter, "a hedge against amnesia for the next generation".