Tell us something we don't know: why science can't show us much about art

I am happy to announce a new annual award, the Vincent Prize for Scientifically Proving the Bleeding Obvious about Art History. The first winners are the researchers who, the papers tell us, have used chemical analysis of Vincent van Gogh’s paintings to reveal the astonishing fact that – get this – his art changed after his mental breakdown in late 1888.

Well knock me over with a virtual feather. Without this research, I would never have noticed that the golden glow of Sunflowers, which Van Gogh painted in a blaze of optimism in the summer of 1888, while looking forward to Paul Gauguin joining him in the Yellow House, communicates a rather different mood to the spiky, agitated lines and violent greens of Long Grass with Butterflies, painted in 1890 in Saint-Paul Asylum.