In the past 10 years Anthony Caro has made it so much clearer what divided him from Minimalists in the 1960s. His use of welded steel in those years might have made him seem generically similar to artists like Judd, but he was always more emphatically metaphorical, illusionistic, graceful - more humanistic.
It is no surprise, then, to find him in this, his 80th year, exploring once again the territory first introduced in the Trojan Wars series, and extended in the more recent Barbarians, and making frankly traditional, representational sculptures using a combination of baked clay and steel. But does this represent progress?
The group of 16 new sculptures on view for a short time at Kenwood are dominated in scale and mood by Witness, a monumental figure comprising several flat sections of clay that have been slapped on and scored like paint before baking. Polished steel bars rise up like fangs in front of it, and its hand is bent over its mouth in a gesture of pathos or terror.
It is a wartime scene (inspired, apparently, by Goya), and its mood pervades the rest of the sculptures, which range from tables stacked with traditional still lives (works like Summit Games and Provisions), to the fencelike, quasi-architectural Messages, to the long, low Shelter.
They are sculptural collages: buoyant, vigorous combinations of fat, soft and puffy baked clay with the denseness of metal. The more they approach the abstract quality of Cubist collage, and the more the elements retain their individual character, the more they succeed.
Lawmakers' Table is a too-chunky platform of clay and sheet metal that cannot adequately suggest books and papers, whereas Orator, with its six stout legs and its round cloud of clay and curves of metal, beautifully satirises the puff and gesturing of speechifiers.
Caro first began to use baked clay in this fashion in the early 1990s as a way of injecting mass into his work (his previous welded steel sculptures were like line drawings in their lithe weightlessness). But these latest works seem just too heavy, their physical bulk only puffing up the portentousness of their titles. Displayed in the Orangery at Kenwood, many look rather as if they are waiting to be dispersed about the grounds, to sit and grow mossy: they seem uncomfortably sheltered indoors, and the room's warm ochre walls and wooden floors rob their colour of its own quality.
Unfairly perhaps, one finds oneself comparing them to his earlier work, and the comparison is not flattering. Caro has accurately described the difference, likening his earlier sculptures to adverbs and the later to nouns. 'Now we're in a more matter-of-fact time, ' he says. 'We need some meat.' Fans of his earlier years may wish he had returned to a leaner diet, but Caro says he has to move on: 'I need to do something that gives me problems.' Well, few of us will be saying the same at 80.
Morgan Falconer is a writer in London. A new book by Julius Bryant, Anthony Caro: A Life in Sculpture (Merrell, £14.95), accompanies the show