In “Sideways Music”, Ned Markosian presents the aesthetic value variance of sideways music as a case against what the Spacetime Thesis—the thesis that time is one of four similar dimensions that make up spacetime. Critics have already raised worries about the premises of his argument. In this paper, I focus on Markosian’s assumed aesthetic realism. I argue that there is a version of aesthetic realism—a version that admits aesthetic value gluts—that is consistent with both the Spacetime Thesis and the aesthetic (...) variance of sideways music. If this is right, then sideways music may simply be a non-issue for proponents of the Spacetime Thesis. (shrink)