ABSTRACT
The vast majority of affixes in the languages of the world evolve from independent words by a gradual process of change called 'grammaticization' or 'grammaticalization' (Bybee, Perkins, & Pagliuca, 1994; Heine, Claudi & HUnnemeyer, 199 I; Heine & Reh, 1984; Heine & Traugott, 199 I) . In the gradual progression from a lexical morpheme to a grammatical one, changes occur in the phonological shape of the morpheme, its meaning, and its grammatical behavior. A well-documented instance of this type of change is the development of the future tense in Romance languages such as Spanish and French. A periphrastic construction in Latin consisting of an inflected auxiliary habere 'to have' and an infinitive yielded a meaning of obligation or predestination:
amare habeo 'I have to love, I am to love' love+inf aux+ I s
The auxiliary reduces phonologically and comes to appear consistently after the infinitive (where previously it could occur in various places in the clause). In Old Spanish we find the construction indicating future:
amar he 'I will/shalllove' love+inf aux+ Is
The auxiliary is written separately from the infinitive because at this stage other morphemes could come between the two; for instance, the object pronoun:
amar 10 he 'I will love him' love+infhim aux+ls
Later this possibility disappears and the auxiliary becomes an actual suffix to the verb:
10 amare 'I will love him' In this process the grammaticizing morpheme undergoes phonological
reduction (e.g., from habeo to he to e), its position becomes fixed, it fuses with the verb, and the whole construction takes on a more abstract, grammatical meaning.
