Grey. It makes no statement whatever; it evokes neither feelings nor associations: it is really neither visible nor invisible. Its inconspicuousness gives it the capacity to mediate, to make visible, in a positively illusionistic way, like a photograph. It has the capacity that no other colour has, to make 'nothing' visible.

I believe that he knew more what he was doing. I might be absolutely wrong about this, but that was my impression.

I don't create blurs. Blurring is not the most important thing; nor is it an identity tag for my pictures.

In 1981, I think, for the Kunsthalle in Düsseldorf. Before that I designed a mirror room for Kasper König's Westkunst show, but it was never built. All that exists is the design - four mirrors for one room.

When I paint from a photograph, conscious thinking is eliminated. I don't know what I am doing. My work is far closer to the Informel than to any kind of 'realism'. The photograph has an abstraction of its own, which is not easy to see through.

... landscapes or still-lifes I paint in between the abstract works; they constitute about one-tenth of my production. On the one hand they are useful, because I like to work from nature - although I do use a photograph - because I think that any detail from nature has a logic I would like to see in abstraction as well.

Well, the beginning is actually quite easy, because I can still be quite free about the way I handle things - colours, shapes. And so a picture emerges that may look quite good for a while, so airy and colourful and new. But that will only last for a day at most, at which point it starts to look cheap and fake. And then the real work begins - changing, eradicating, starting again, and so on, until it's done.