Meaning both ‘also’ and ‘only’? The intriguing polysemy of Old Italian pur(e)

Italian "pur(e)" seems to be quite peculiar among focus markers, since diachronically it displays the whole span of functions, from non-scalar exclusive to non-scalar additive. It is still an open question as to whether or not at some stage of its history "pure" enjoyed such an extended (nearly self-contradictory) polysemy synchronically too (while it is surely not the case for the contemporary language). The present investigation, based on the large corpus of the Opera del Vocabolario Italiano, casts some doubts on this possibility for Old Italian (approximately until the end of 14th century). Moreover, it surveys the very wide polysemy of "pure" beyond the functions of focus marker proper, and proposes several different evolutionary paths, among which some involve also non-focus marker uses as intermediate steps.