I was once told that the greatest of all the surrealists, Rene Magritte wrote sub-Heideggerian philosophical tracts, but I've never been able to confirm it. Translations would be a commercial triumph in the culture studies departments I suspect, though no doubt the work itself would be a disappointment.
Magritte also painted for his local branch of the Communist Party, though one suspects that the embarrassed branch secretary would have just stuck them away in a corner somewhere, to be lost forever, as they hardly suited the socialist realism policy. Some plodding antiwar allegories survive.
-- Jim heartfield