Gram - SEAS

100 5 The hypothesis of unidirectionality
lexical item to morphology. Rather, lexical items or phrases come through use in
certain highly constrained local contexts to be reanalyzed as having syntactic and
morphological functions. Schematically, this can be characterized as:
lexical item used in specific linguistic contexts > syntax > morphology
The lexical items that become grammaticalized must first be semantically general
and serve commonly needed discourse functions. They then become syntacticiilly
fixed (they become constructions), and may eventually amalgamate morphologically,
say, as stem and affix. The basic assumption is that there is a relationship
between two stages A and B, such that A occurs before B, but not vice versa. This
is what is meant by unidirectionality.
Before proceeding, it should be mentioned that the unidirectionality in question
is not the same as what E. Sapir called "drift," although it has some similarities.
In a famous statement, he said: "Language moves down time in a current of its
own making. It has a drift" (1921: ISO). Even if we were to emend this statement
to acknowledge that it is not language that changes, but rather language users
internalize different rules of grammar over time (see Section 3.2), there would
still be a fundamental difference from what is meant by the unidirectionality of
grammaticalization. Sapir was interested in the fact that English was losing case
inflections on its pronouns (e.g., the who-whom distinction was losing ground),
and that English was also becoming more periphrastic, for example, the possessive
genitive was being replaced by of I While Sapir was thinking of language-specific
changes, and, within languages, of highly specific phenomena, other linguists later
showed how the separate phenomena he discussed for English were in fact part
of the same thing (case loss and periphrasis go hand in hand), and indeed part
of larger typological shifts. R. Lakoff, for example, focused on drift "defined . ..
very loosely as historical fluctuation between syntheticity and analyticity" (1972:
179), that is, on fluctuation between bonded ness and periphrasis, while Vennemann
(1975) focused on shifts from OV to VO order. Lakoff's summary of Sapir's notion
of drift as "a metacondition on the way in which the grammar of a language as a
whole will change" (R. Lakoff 1972: 178) serves well to differentiate "drift" from
unidirectionality. Drift has to do with regularization of construction types within a
language (see also Malkiel 1981), unidirectionality with changes affecting particular
types of construction. Unidirectionality is a metacondition on how particular
grammatical constructions will change.
5.2 Generalization
Among characterizations of grammaticalization, the following statement
is typical: "It is often observed that grammatical meaning develops out of lexical