Teeth. We all have them, or start out with them. We’re supposed to take care of them, so we can flash a smile. But for Francis Bacon, they are a glimpse of death in a living human face, a white hardness that will persist when all our soft matter is gone. In Study of the Human Head, a man in a dark jacket smiles out with perfect teeth. Then you realise Bacon has superimposed an x-ray image of the human head on to this living man. It is the grin of a skull.
The National Portrait Gallery has assembled a truly biting show of Bacon’s portraits and meditations on portraiture. Not only is it the best Bacon show I have ever seen, it also answers all questions about his greatness. Was he a genius or a showman, a seer or sensationalist? Critics started arguing from the moment, in the 1940s, when he burst out of nowhere to shock a wartime London you’d have thought unshockable. The critic John Berger accused him of “horror with connivance”. Fans of fellow artist Lucian Freud still sniff that his friend Bacon was a slapdash, melodramatic artist. And they’d be right – but only if the definition of a great portrait was a recognisable depiction.