‘ Colours are absolutely interdependent. They interact, merge and generate new colour in such complex ways that to make them work, one has to think of them in groups, in clusters, in relationships and push them around until they become not only several things, but also simultaneously one thing, something which isn’t form or shape as such, but rather an activity, an activity which comes out at you, that can throw something off the canvas, suspended as it were between you and the painted surface. ’ -Bridget Riley
detail from 'The Arnolfini Portrait' by Jan van Eyck (1434)
The National Gallery, London
