Violent and original dreams

Will Self on JG Ballard in Granta 107:

Ballard, the most outlandish of fictional imaginers, had always dug out his wellspring by the hearth, and remained the perfect exemplar of Magritte’s dictum: a bourgeois in his life, a revolutionary in his dreams.

Another maxim, expressing a similar sentiment, is attributed to Flaubert. From his entry on “Wikiquote”:

Soyez réglé dans votre vie et ordinaire comme un bourgeois, afin d’être violent et original dans vos œuvres.

Be regular and orderly in your life like a bourgeois, so that you may be violent and original in your work.

[Letter to Gertrude Tennant (December 25, 1876)]

My boring 12:38 a.m. EST questions: was Magritte alluding to Flaubert? Was he improving on Flaubert, changing “oeuvres” to “dreams”, and “violent/original” to “revolutionary”?

Should Self have quoted Flaubert, and not Magritte? Or do the revolutionary dreams that emerged from JG Ballard’s bourgeois life have more to do with the painter than the novelist?