Many of them surely do, but they are not the ones who occur to me, not the ones who come to mind, when I think of writers who have a facility with, or are conversant in, a particular subject; no, I think then of history’s great fiction writers, because, within the broader genre of prose (to which both fiction and non-fiction belong), writers of fiction who excel at fiction seem to me more capable of investing their ‘non-fictive’ passages with a style that belongs to them; and which style, strangely enough, seems to add an extra layer of ‘truth’ to whatever subject they have chosen to address themselves to, even if that extra layer is an illusion.