The world of visual art has its contradictions, and one of the most perplexing is the taboo on appropriation. In the humanities, to reference other people’s intellectual ideas is considered to be good research. In music, training in instruments and the adoption of a musical genre is seen to expand possibilities. In cooking, learning existing recipes leads to refinement. In the visual arts, however, appropriation is generally seen as a sign that the artist is a copyist lacking in creativity. The taboo on appropriation was starkly revealed in 2010 when it emerged that Sam Leach’s Proposal for a Landscaped Cosmos,…