One of the many questions about the art world probed by Hari Kunzru in his new novel Blue Ruin is the notion of provenance in the context of a working relationship between a well-known artist and his paid assistant. Does an assistant's creative output in any way belong to them? Or does it belong solely to the artist for whom they work?

Artists have long utilized the support of assistants, also called fabricators, but these relationships have changed dramatically over time. The great masters of old carefully trained their assistants as apprentices, so their working relationships were closer to that of teacher and student. In their masters' studios, assistants would be given opportunities to hone their own skills. There are many examples of assistants developing their skills alongside their teachers. The iconic Mona Lisa painting by Leonardo Da Vinci has a twin image, today on display in Madrid's Prado, that many believe to be painted by one of Da Vinci's apprentices ...