Prichard seems to have thought […] that the normativity of morality cannot be explained at all. But that does not follow. Even if there is no instrumental explanation of its normativity, there may be an explanation of some other sort. It would truly be unsatisfactory if there was no explanation at all. It would be a bad blow to philosophy to find there are inexplicable facts.

John Broome, ‘Reply to Southwood, Kearns and Star, and Cullity’, Ethics, vol. 119, no. 1 (October, 2008), p. 98