How Michael Craig-Martin changed a glass of water into a full-grown oak tree

‘Of all the things I’ve drawn,’ Michael Craig-Martin reflects, ‘to me chairs are one of the most interesting.’ We are sitting in his light-filled apartment above London, the towers of the City rising around us, and we are discussing a profound question, namely, what makes an object a certain type of thing? Or to put it another way, what makes a chair a chair?

Craig-Martin’s career has been characterised by what he calls ‘my object obsession’. There will be chairs on view in the grand retrospective of his work which is about to open at the Royal Academy, but by no means only chairs. The galleries will be filled by a cavalcade of mundane bits and pieces, among them safety pins, filing cabinets, forks, smartphones, pliers, light bulbs and buckets. All of these are drawn with a thick, clear black line and painted in vivid, joyous and completely non-naturalistic colours.