 Explications of the concept of music usually begin with the idea that music is organized sound. They go on to note that this characterization is too broad, since there are many examples of organized sound that are not music, such as human speech, and the sounds non-human animals and machines make. There are two further kinds of necessary conditions philosophers have added in attempts to fine tune the initial idea. One is an appeal to “tonality” or essentially musical features such as pitch and rhythm (Scruton 1997: 1–79; Hamilton 2007: 40–65; Kania 2011a). Another is an appeal to aesthetic properties or experience (Levinson 1990a; Scruton 1997: 1–96; Hamilton 2007: 40–65). As these references suggest, one can endorse either of these conditions in isolation, or both together. It should also be noted that only Jerrold Levinson and Andrew Kania attempt definitions in terms of necessary and sufficient conditions. Both Roger Scruton and Andy Hamilton reject the possibility of a definition in terms of necessary and sufficient conditions. Hamilton explicitly asserts that the conditions he defends are “salient features” of an unavoidably vague phenomenon.