Yes, there is a wonderful moment of excitement in looking at something that purports to be Rubens and it isn’t a Rubens, and it isn’t a Rubens, because it’s a copy by Delacroix, because Delacroix has made subtle alterations and so on. It tells you so much about Delacroix. It might not tell you anything about Rubens. And it’s only the surface of it, the subject that has given you the misleading thought that it is Rubens.

I have a little painting, of which I’m very fond, by Matthew Smith, and it’s after Delacroix, so it does exactly the same thing. It tells me so much more about Matthew Smith than it does about Delacroix. There’s a painting there which is a copy of Ribera, by Glyn Philpott, and it’s a very instructive little thing about Philpott, and you look at it and you say, but this is a Ribera composition, this is Ribera colour and so on, but it’s not Ribera’s scale and it can’t possibly be Ribera, it… just look at it. And then you have to do this… and sometimes it’s the most difficult work in the world to… when you have one really good painter working on another really good painter, because the qualities of both are coming into play and lending confusion. Then you need some kind of proof, which will be either documentary or a letter recording something, or, as in the case of the Philpott, there’s an inscription on the back... his signature.

So no, that’s… but that’s an entirely different matter from the forger who is setting out to deceive.