  Jean-Paul Sartre (1938, 1940) has often been credited with the idea that works of art are illusory (in the sense of systematically being the object of some sort of error about their mode of existence), but it is not obvious that this is the best interpretation of his remarks on the topic. Sartre declares that Beethoven’s Seventh Symphony “is outside of the real, outside of existence” (1940, 371, my trans.). He also says that we do not really hear the symphony at all, but only hear the composition in our imaginations. Such statements can be read as being meant to debunk a widespread illusory belief in the existence of musical works; they also hold open the possibility of imagining works without believing in their existence, in which case the putative illusion is not necessary.  One of the possible targets of Sartre’s remarks is a kind of idealist doctrine discussed below. For an informative discussion of Sartre’s views on the subject, see Peter V. Lamarque (2010, chapter 10); and for additional background, see the entry on existentialist aesthetics.