Music can put us in the presence of something that has no place in this world, and which moves in a world of its own. And it can do this in a way that seems both orderly and personal, moving with a complete necessity that is also a kind of freedom. Two features of music contribute to this effect. First, the space of music, in a listening culture, is what I call an ‘acousmatic space’: it is a space full of movement and fields of force in which nothing actually moves, and of which we ourselves could never be a part. In a mysterious way the order of music transforms sequences of sounds into melodies that begin and end, chords that occupy whole areas and gravitational fields that push and pull in ways of their own. I have elaborated on this in The Aesthetics of Music, and I think one conclusion to be drawn is that musical space is a space in which things move with a singular freedom, precisely because it contains no obstacles – no part of it is occupied, in the way physical space is occupied, but all of it is open.
Secondly, the virtual causality that operates in musical space is or aims to be a causality of reason. In successful works of music there is a reason for each note, though not necessarily a reason that could be put into words. Each note is a response to the one preceding it and an invitation to its successor. Of course, sequences in music may sound facile, mechanical or arbitrary, so that the listener has no sense of a reasoned progression. But when that happens we are apt to dismiss the music as trivial or meaningless. Real music is not a sequence of mechanical movements but a continuous action, to which the ‘why?’ of inter-personal understanding applies.
Roger Scruton, "Effing the Ineffable".