Since then, and especially in the past few years, Craig-Martin has become even better known as a teacher. Currently, he is Millard Professor of Fine Art at Goldsmiths College and patron saint of the new generation of super-successful Goldsmiths graduates. But, while the eyes of the world have been fixed on careers that he nurtured, his own achievements have rather slipped out of view.
Until this week, that is, when he returned to the scene with a clutch of new exhibitions in London. At the Waddington Galleries in Cork Street a selection of recent paintings are grouped under the baffling title Innocence and Experience - they have little to do with either and nothing to do with Blake. Across the street, the Alan Cristea Gallery has mounted a mini-retrospective of his prints, some of which will also be on show at the London Original Print Fair at the end of the month, and round the corner in New Bond Street he has become the first artist commissioned by Jigsaw to make a temporary installation in their flagship shop.
So, what has Craig-Martin been up to while his former students have been stealing the headlines? His new paintings are big, bold and very colourful. They depict everyday objects drawn in heavy black outline floating in bright fields of pure colour - lime greens, shocking pinks and powder blues - with the size of the drawn object relating only to its place in the picture rather than to actual scale (large at the front - the foreground; small at the back - the distance). These objects are then coloured in to create maximum contrast or clash with the background.
The effect is a bit like walking into the pages of a child's colouring book, or a first alphabet without the guiding a, b, c.
The Waddington exhibition is dominated by three huge paintings: titled Looking, Learning and Knowing. Two of them (Learning and Knowing) depict the same selection of objects (chair, table, step-ladders, bucket, fire- extinguisher, metronome, torch and globe) but the positions of the objects are reversed from one picture to the next. Clearly, if one pays any attention to titles, this reversal is meant to mean something but it's rather hard to know what. More effective, or at least more intriguing, are the Innocence and Experience paintings, where the objects are arranged in threes so that there seems to be some kind of relationship between them: parts of a puzzle, perhaps, or the ingredients of a weird story.
The ideas behind these paintings, as far as I can work them out, seem rather too simple for the man who gave us An Oak Tree. His teaching success has proved that he is an inspirational figure and his curating of Drawing the Line at London's Whitechapel Gallery in 1995 showed the brilliance of an inventive and intelligent imagination, but there are few signs of these attributes in these recent paintings.
Craig-Martin himself has pointed to their intentional ambiguity. These pictures, he has said, are "neither hierarchical nor didactic, neither narrative nor allegorical, but all these possibilities are implied. Things both connect and don't connect." A sentence that seems to mean less and less each time I look at it. Rather like these pictures. At a first glance, they struck me as simple but fun. At a second, I was looking and hoping for something more; but, at a third, I realised that the something just wasn't there. What you see, in other words, is all you get. `Innocence & Experience': Waddington Galleries, 11 Cork Street, London W1 (0171-437 8611) to 8 March