The only thing to do on leaving the Goya show at the National Gallery – unless you can afford to buy another ticket and go straight back in – is to find something good to read about the painter as fast as you possibly can. But what? So much art writing is so unbelievably bad: boring, jargon-filled, devoid of any wit or insight. Either its practitioners believe scholarship and style are mutually exclusive – a very stupid form of intellectual snobbery – or they simply don’t know how to write.

But, lucky us, the Australian critic Robert Hughes wrote a biography, Goya – and so, we are saved. Back at home, searching out his accounts of the paintings I’d just seen, relief flooded in. While I’d only been able to stand stupidly in the gloom, jaw swinging, before The Family of the Duke of Osuna, Hughes unfailingly has the right words. Describing Goya’s life-size self-portrait of 1815, he writes of the “cannonball of flesh and bone, lightly filmed… with the sweat of concentration”. A cannonball? Yes, this is exactly it. “Goya,” he notes, “was an artist wholeheartedly of this world. He seems to have had no metaphysical urges. He could do heaven, but it was rather a chore.” That last sentence: how clearly it rings. Hughes’s cadences, born of his Jesuit education, are un-improvable.

When I interviewed him in New York in 2006, Hughes was unaccountably mean to me. But this had no effect whatsoever on my admiration for him; if anything, it only deepened. And so it goes on. Each morning, just now, I listen anxiously for the post, hoping for the arrival of a parcel from America. The Spectacle of Skill, a new collection of his work, includes the (unfinished) memoir Hughes was writing when he died in 2012 – pages I long for, but will have to eke out, as the back patient does his diazepam.