A distinguished dramatist once surprised me by lamenting the plight of Harold Pinter. 'All other dramatists', he announced, 'can go off and write any type of play they please - farce or history, polemic or romance. But Harold Pinter has to write a Harold Pinter play. It must be hell for him.' This was an affectionate joke, but a joke which expressed a truth. Pinter's plays are instantly recognisable and particular. 'Pinteresque' is a word that has entered the language. His voice - whether it be combative cockney, or expressing the unexpected associations and leaps of memory - is very much his own. His content - the unknown threat, the confrontation in the confined space, whether it be territorial, or the personal tensions of the subconscious - has hardly changed in forty-five years. The threats have always been political, metaphors of power. Pinter is the champion of tolerance and compassion in the brutal jungle of life, the seeker after clarity in the confusions of memory. The presence of imminent violence, of a breakdown bound to happen, haunts all his plays. Speech is at cross-purposes and combative; charm is possessive; concern contains a hidden mockery; even love is often a violation. But all these threats are subtle - never palpable. Above all, they are ambiguous. Tension may finally explode when a man's head is split open by a blow from a walking-stick. But before this, the demands of social conduct have been observed in their full contradictions. To mock someone, to take them on, only scores points if the hatred is disguised with charm, and the hostility with wit. The victim must never be sure that the antagonist is his enemy.