General Principles

A. Heine (1985)

The more a form is grammaticalized:

1. the more it loses in semantic complexities, functional significance, and/or expressive value

2. the more it loses in pragmatics and gains in syntactic significance

3. the more reduced is the number of members belonging to same morpho-syntactic paradigm

4. the more its syntactic variability decreases => its position in the clause becomes fixed

5. the more its uses become obligatory in some contexts and ungrammatical in others

6. the more it coalesces semantically, morphosyntactically and phonetically with other units

7. the more it loses in phonetic substance

B. Hopper

1. Layering: within a broad functional domain, new layers are constantly emerging => yet, older layers are not discarded => grammaticalization does not proceed by eliminating old forms and substituting new ones but by crowding the fields with subtly differentiated forms

2. Divergence: when lexical form undergoes change to clitic or affix, the original lexical form may remain an autonomous element and undergo same changes as ordinary lexical items => grammticalization does not entail disappearance of its lexical use

3. Specialization: within a functional domain, at one stage a variety of forms with different semantic nuances is possible; as grammaticalization occurs, this variety of formal choices narrows and the smaller number of forms selected assume more general meanings

4. Persistence: when a form undergoes grammaticalization from a lexical to a grammatical function, so long as it continues to have a grammatical role, some traces of its original lexical meaning tend to adhere to it

5. De-categorization: grammaticalization always involves a loss of categoriality and proceeds in the following direction: N/V => another category, never the reverse