John Constable's reputation is never going to rest on his portraits. This painter of rainswept castles, master of cornfields and titanic genius of landscape was hamfisted when it came to painting people. Constable's portraits are interesting because they are by Constable, and because they depict the faces closest to him in his little provincial English world. In that sense, they become extremely moving - strange, clumsy, revealing documents of a life in Regency England.
This is what makes the identification of a picture of Constable's father by the curators of the National Portrait Gallery's new exhibition so intriguing. When we look at Constable's portraits we're looking for psychology, for emotion - and the emotional difference between a portrait of his father and his schoolmaster is obviously vast. If Anne Lyle and Martin Gayford are right to claim this is not after all a local educator but Golding Constable, it suddenly becomes a far more expressive work. Doesn't it? Or do we imagine we see a hard shine to the skin, a cold glint in the eye? It's tempting to compare it with Cézanne's great portrait of his father in the National Gallery. Yet if it really is just Constable's schoolteacher, it's still massively characterful.
The view of his mother does not have as much emotional strength as the portrait of his father - does this mean the curators are wrong to claim it's an 1805 original? In fact, I can see why they reject the idea that it's a copy. Who would copy such an unpretentious work?
Both paintings have a naive quality - and yet, they also have a brilliance. The flesh on the man's portrait has a mottled vividness that's in keeping with Constable's skies. It's fascinating to see an artist come so close to visual innocence while at the same time being a genius. Here, you feel, is the young artist who refuses to lie, to flatter appearances - and who will never betray the little world he so loves.
