Tate Modern: a shock to the old

It is only a slight exaggeration to claim that if I had a pound for every occasion on which I have been assured that the inexorable rise of Tate Modern and its kin all over the globe has been counterpointed by a mournful decline in the fortunes of the Old Masters, I would be a rich man. Such statements need to be confronted with large doses of merciless scepticism.The first point to make, before properly getting down to business, is that the house of art has many mansions, and that its constitu