This paper is focused on one of the key questions constituting the medieval debate about the ontological status of artefacts, which has to do with the productivity of art. We ordinarily speak about artefacts, such as statues or chairs, as produced by their artificers, and Aristotle describes art in general as a productive habit. In the first part of the paper, I look at how the proponents of the realist view of artefacts argue that the productivity of art can only (...) be explained if we endorse their view, on which by producing an artefact an artificer brings about a new thing in the world, which is distinct from the natural things used in its production. I then turn to the reductionist account of artefacts and examine how its proponents want to show that the productivity of art can be preserved without positing that an artefact must be a new thing in the world, distinct from its natural components. In the final part of the paper, I look at one of the further corollaries of this debate, which has to do with the connection between the productivity of art and natural change. (shrink)