Prépositions françaises en diachronie : une catégorie en question

Since the 17 century, French has had both the categories of adverbs and prepositions, each represented by specific morphemes. In Old French however, this situation was different: one morpheme could then function as preposition, adverb, particle, verbal prefixe and subordinating element. In the light of recent theories concerning changes of grammatical categories and the notion of 'emergent grammar', a matter of concern should be whether these different categories have to be distinguished for Old and Middle French, or whether these morphemes are to be considered as making part of multi-functional or even multi-categorial paradigms. In the latter case, each paradigm would express one notion or a series of related notions. A concrete analysis of the usage of four such morphemes, aval, par, tres and en, from 1000 to 1500 shows how these 'prepositions' evolve from multi-categorial to mono-categorial usage. This reduction of pluri-categorial morphemes in French can be explained by a more general change at the level of the French grammatical macro-system, leading towards an increasing iconicity, where one function is expressed by one single for