"Comedy deserves to be taken seriously," wrote Aldous Huxley, in 1924, before going on to denounce those "lesser exponents" of the genre who specialise in "triviality, ugliness and vulgarity". Three years later, The Jazz Singer ushered in a new era of "talkies" that would change the way Hollywood made comedies, as slapstick and sight gags were overtaken by witty banter.

Today the triviality, ugliness and vulgarity are back. Instead of wit, we are served a relentless stream of expletives, dick jokes and toilet humour. This is what passes for comedy in mainstream American cinema. The most frightening part is that it's probably the result of extensive market analysis which has discovered a vast, brain-dead audience for this kind of thing.