Sharp, piercing, inhuman, intimidating, industrial, modern, overwhelming, muscular. These words sum up my first experience of Sir Anthony Caro's work. It was 1970 and I was visiting Boston, Massachusetts for the first time. Ranged around the harmonious and highly architectural Copley Square were a series of his sculptures. With their rough, orangey-brown metal surfaces they were far removed from the traditional sculptural vision of polished marble; to me these towering abstract objects resembled the components of a futuristic experiment, or things that had been left to moulder in a warehouse and then rediscovered years later. They stood not on some distant plinth, but uncompromising and confrontational on the ground; a new language in sculpture.
Later, when Caro talked about these works to the critic Peter Fuller, he said they "incorporated space and interval so you could not grasp them from a single view: you had to walk along to take them in. They involved time like music does". For me, walking around them was an experience which convinced me that I wanted to know more about art; anything that could give me such a powerful sensation was worth learning about.
Thirty-odd years later I am thinking about my early experience as I arrive to meet one of Britain's most senior sculptors at his Camden Town studio, the same one that he has occupied since he came to London in 1953 after completing his "apprenticeship" with Henry Moore. He is dressed simply in khaki trousers and a green polo shirt; his neat and trim appearance somewhat at odds with the experience I have had meeting other sculptors: no thick neck and glowering eyes here, rather a neatly clipped beard and expressive twinkling eyes. He looks incredibly boyish and fit for an 80-year-old man and is excited about the exhibition of his ceramic pieces and "assemblages" which opened recently at Kenwood House in Hampstead. Further ahead there is also the prospect of a much larger retrospective which will open at Tate Britain in 2005.
Over coffee and chocolate biscuits around a large conference table we discuss his career. Caro - who was born in New Malden, Surrey, in March 1924 - knew he wanted to be an artist at an early age. "But in those days it was something you did for fun, it wasn't something you made a life of; you made a life of doing a job," he says. His father wanted him to go into the family business - stockbroking - but when the young Anthony demurred he encouraged him to try architecture instead. Caro had a go but it didn't engage him. Eventually he went to Cambridge to study engineering and then joined the Navy towards the end of the war. But still he wasn't happy and in the end his father gave in. "If art is what you want to do," he said, "you'd better do it."
Caro now credits his determination to do well partly out of a sense of wanting to prove to his father "that it wasn't just a game, and that I was a serious person". He was turned down by St Martin's and landed up at the Royal Academy Schools; sadly his father died when he was a student so he never got the chance to prove to him that he could succeed in his chosen field.
When Caro left the Royal Academy in 1951 he knocked on Henry Moore's door in Hertfordshire and asked if he could be his apprentice. Why Henry Moore, I ask. "He was the best, the most forward-looking sculptor," he explains. Caro's strongest memories of that period are of making drawings on Wednesdays - which Moore would criticise on Thursdays - and of Moore's library, where he saw Surrealist art and sculpture from primitive African and Oceanic cultures. But after two years he moved on: "I felt the time had come to be a little more independent." Caro and his painter wife, Sheila Girling, decamped to London and moved into the house in Hampstead where they still live today.
Caro stayed in London for the next six years, teaching at St Martin's, the college that had previously rejected him, and working through the ideas he had developed with Moore. The result was a series of large rugged nudes which acknowledged the work of Picasso and the primitives that he had encountered in Moore's library. In 1960 he was invited to teach in the US at Bennington College, Vermont. In an interview in 1988 Caro admitted that by 1959 he "had reached the end of that sort of Moore-influenced art; I felt I was scraping the barrel. I wanted to make something which was going to be a step forward, not a reiteration of something which had already been said." By this time Caro claims that Moore was no longer as big an influence on his work as Picasso. He was exploring the many potential pathways of modernism.
Around this time Caro took a trip to New York and the conversations he had there with painters such as Kenneth Noland, critics like Clement Greenberg and sculptors such as David Smith, were to have a profound effect on him. He started by making works like Twenty Four Hours (1960) - now in the Tate collection - which were purely abstract, constructed of bolted and welded scrap steel cut into geometric shapes. But it was in taking the work off the ceremonial plinth and standing it firmly on the ground in the viewer's own space that Caro made his most significant contribution. His work of this time tussled with the same problems that the minimalists, and particularly Barnett Newman, were confronting in their paintings: Caro wanted to remove all the nostalgic and historical elements from his work and make something truly modern.
Going to work in America was a courageous thing to do and it opened Caro up to all sorts of new influences. When I point out what an important example he set for other artists, he shrugs modestly. To him the sculptors who were influenced by him were the formalist ones, "like Tim Scott, Phillip King and Bill Tucker", he says. "But then others came along like Richard Long and Gilbert and George, and they went their own way." In fact, Gilbert and George claim that Caro had a profound effect on their work. When I tell him this he says: "I think where I was influential was in saying, 'Let's look at sculpture, you don't have to do this and you don't have to do that, it doesn't have to be bronze, it doesn't have to be a hero, it doesn't have to be a sculpture'."
All these ideas are seminal in the history of late 20th-century sculpture: challenging the orthodoxy in materials, opening the door for experimentation, using steel and other industrial products which were not traditionally associated with the art form. Would the great American artist Richard Serra ever have started rolling his steel without seeing Caro's 1964 show at the New York gallery of Andre Emmerich, I wonder?
But perhaps the most important of Caro's statements is the one in which he challenges the concept of the "hero". Historically, public sculpture had been primarily about commemoration. The Festival of Britain in 1951 had for the first time allowed a redefining of what could be sculpture, but there was still the perception that plinths should contain recognisable images. Caro, however, was totally opposed to this. In fact, he was against any interpretation of figuration in his work, as he makes clear when I ask him about the assertions of the critics David Sylvester and Peter Fuller that he incorporated some of Moore's reclining figures into his earlier works. Caro rejects this, saying: "It's simply wrong. If my things look like reclining figures, it's by chance. I don't see it. It's the one thing I didn't want them to be and I still don't want them to be seen that way now." What he does want to be remembered for, he says, is for doing away with the pedestal, "killing statuary, bringing sculptures into our lived-in space." This had a tremendous effect, opening up the way for some of the most radical work - including performance art like Gilbert and George's Underneath the Arches - that has happened since. As Caro remembers, "people then started saying breathing could be sculpture; people took it a long way, much further than I did."
Leaving the comforts of the conference table behind we walk into the large lofty studio where Caro continues to work each day. Two assistants are bent over welding torches. Yellow sparks and a smell of burning metal fill the air. They are welding together a steel beam that will eventually be part of one of Caro's "assemblage" pieces. Caro says that for him the most important thing about making new work is that "you want to challenge yourself - the best sculpture is about self-expression. Nothing is set in stone." There's some irony in this statement because Caro is one of those sculptors who has used many materials but has rarely - if ever - used such a traditional material as stone. His preference is for steel, bronze, paper and, most recently, terracotta.
At the time I visited, the work for Caro's Kenwood show was arranged in a room off the main studio, where we looked at the pieces he has assembled using terracotta. Caro began working in the red clay in France several years ago when he fired a variety of pieces with little idea of how he might use them. We pause in front of Still Life, a traditional arrangement with clay shapes that resemble apples and pears. What saves this piece from being a cosy arrangement is a large slab-like form on one of the sculpted tables. It is reminiscent of a skull by Picasso. Caro admits that he often draws on art history for inspiration and reference. "All artists have this pool of knowledge, you just have to know when to use it," he says.
This flirtation with figuration is something that has reappeared throughout Caro's career in different ways. He admits that recently he has started admiring the Surrealists, whose work this sculpture also acknowledges. The largest piece in the Kenwood show is Witness, a clearly figurative piece which, although it seems about nine feet tall, is not triumphant. Caro has portrayed the figure with his face obscured by his hands contained in a steel stockade; a man ashamed of his heroic acts. It is a clear indictment of war. The show is called "The Way It Is"; and Caro is clearly making a comment on our current political predicament. "An artist cannot ignore the times he exists in," he says quietly.
After a brief detour through a room filled with miniature versions of Caro's work we arrive back in the main studio and discuss his future plans. After the Kenwood show he intends to make some large "assemblage" works using machine parts, a form of sculpture reminiscent of some early 20th century pieces by Picasso and Duchamp. He instructs his two assistants to put one of these together to show me. It has three parts: one part is a recognisable drilling machine; one an enormous chain; the other the steel beam I saw them welding earlier. I tell Caro that this is the first piece of his I have seen which incorporates a chain. "Things have a way of appearing," he smiles.
At the moment it is painted with an undercoat of battleship grey. I ask what colour it will be when it's finished and he calls for a pot of paint to be opened. We all peer in - it is a strange, sludgy apple green. I ask: "Will it work?" "I don't know what is going to happen," he smiles. "We won't know until the paint is on - somehow I think it probably won't work. But we will experiment until it does. I don't want there to be rules."
Caro has not painted his works since the 1960s, when he made iconic works like Sculpture Two, now on show at Tate Britain's exhibition "Art and the 60s". Why did he stop making them, I ask. "I had a show in New York and I thought it was too successful. Why did people like it so much, I wondered. I must be going wrong. So I went into steel and non-colours." This is why Caro is one of the most exciting British sculptors working at the moment: at the age of 80 he is still not afraid of trying new things.
In a letter to the influential American art critic Clement Greenberg in 1969, Caro complained about the price he was paying for having accepted a CBE (he received a knighthood in 1987). Other artists, he explained, had been saying publicly that he had sold out for fame - ironically mimicking what had happened with Henry Moore before him. Caro now says, most tellingly, that "I decided to keep my head down and get back to the studio, which makes me a lot happier."
I wonder how this modest yet self-determined man will deal with the fuss and hoopla that will inevitably accompany his Tate show this winter. Will Caro achieve the international recognition he deserves? Will a whole new generation, I wonder, be inspired to learn about art by these tough, raw objects which are also so full of grace? I think back to my younger self in Boston in 1970, I think of the pleasure that art has given me since, and I hope so. *
'The Way It Is: New Sculptures by Anthony Caro': Kenwood House, London NW3 (020 8348 1286), to 25 July. A new book, 'Anthony Caro: Quest for the new Sculpture' by Ian Barker (Lund Humphries £30), is out now
Karen Wright is the editor of 'Modern Painters'