Response to Geraint Wiggins

In response to the contribution to this volume by Geraint Wiggins, I ask what music theory is for and, argue that, through education and the activity of composers, it has an influence on the very music it aims to describe. I defend Schoenberg from the charge of ignoring musical perception, and claim his music is successful even if not in the way he had envisaged. The music theoretic enterprise, including its mathematical branch, has an effect on musical culture, but that effect might be difficult to predict.