Joel Meyerowitz American, b. 6/3/1938

Two pictures hang side by side on the same wall. The one on the left is in a heavy frame: a woman in a pale dress at a table, a man standing behind her, everything varnished into a warm brown. The one on the right is a window, and in it a woman in purple with a blue umbrella sits smoking on a bench while a man in a cap keeps his back to her, and the trees of the garden carry on behind them in the flat green of a wet afternoon.

Everything a museum is for sits in that rhyme. The painted couple and the actual one are the same couple — a woman looking out, a man not looking, and a century between them changing nothing except the price of the frame. Meyerowitz saw it in the time it takes to walk past, which is the only time such things are ever on offer.

And he saw it in colour, in 1967, when that was still a position rather than a default. The whole picture depends on it: the ochre of the wall against the green of the trees, the purple sweater, the blue umbrella that no monochrome version could have delivered. What looks obvious now was, then, an argument — that colour is where the world keeps most of its meaning, and that a serious photographer had better go and get it.