I believe that you always have to believe. It's the only way; after all we both believe that we will do this exhibition. But I can't believe in God, as such, he's either too big or too small for me, and always incomprehensible, unbelievable.

Perhaps the choice is a negative one, in that I was trying to avoid everything that touched on well-known issues - or any issues at all, whether painterly, social or aesthetic. I tried to find nothing too explicit, hence all the banal subjects; and then, again, I tried to avoid letting the banal turn into my issue and my trademark. So it's all evasive action, in a way.

To believe, one must have lost God. To paint, one must have lost art.

Experience has proved that there is no difference between a so-called realist painting - of a landscape, for example - and an abstract painting. They both have more or less the same effect on the observer.

Composition is a side issue. Its role in my selection of photographs is a negative one at best. By which I mean that the fascination of a photograph is not in its eccentric composition but in what it has to say: its information content. And, on the other hand, composition always also has its own fortuitous rightness.

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.

The first colour charts were unsystematic. They were based directly on commercial colour samples. They were still related to Pop Art. In the canvases that followed, the colours were chosen arbitrarily and drawn by chance. Then, 180 tones were mixed according to a given system and drawn by chance to make four variations of 180 tones. But after that the number 180 seemed too arbitrary to me, so I developed a system based on a number of rigorously defined tones and proportions.