I merely argue, when I see a certain picture, with the paint still wet on it: 'That picture was painted by a certain painter.

I am an expert, and I stake my reputation on it' It's no use telling me that the painter in question died several years ago and was buried with national honours in Westminster Abbey.

I say it couldn't have been so.

I'm a connoisseur.

And if the facts of his death and burial don't agree with the result of my connoisseurship, I say they aren't facts.