Thoughts on Lineage and areality

This week's blogpost will continue the thread about grammatical reconstruction, with some thoughts on lineage versus areality in grammar change. 

In general, change of grammar is supposedly cyclic (or spiralic according to some researchers): over time, typological organization of features in systems recur of are re-established. We may look at this issue both from a long-term and a short term perspective. One thing for a feature is the inherent possibility to be homologous (a simirlarity may depend on inheritance only) or homoplastic (a similarity may depend on internal or areal pressure, caused by various factors). Another thin is whether a similarity is caused by areal pressure or whether it is caused by lineage. A construction or a feature may be indicative of all of all these processes. For instance, a feature like word order is by nature homoplastic (similarities in word order may be due to areal or internal pressure, such as change in order of meaningful elements), but even then, a word order feature may be due to lineage: it has been inherited by ancestry generation after generation, or it is a critial innovation restricted to a specific sub-branch of a tree. Take for instance the verb-initial order in Celtic languages: it is likely that this feature is caused by interal pressure in the verbal paradigm (McCone 1987). Because of this, verb-initiality is a features which is restricted to the Celtic sub-branch and therefore a homologuous innovation of this specific branch, not caused by areal pressure. The feature is entirely independent of other Eurasian verb-initiality. Another example is the Germanic have-perfect. It is a homoplastic typological feature (expressing perfect by an auxiliary construction), which still uses the same cognate root as the auxiliary, the verb *haban. The process took place independently in all Germanic languages, due to parallel drift and possible areal pressure. As before, it is difficult to distinguish areality from lineage.

Very interesting is the process of Indo-European alignment change, from the proto-language to the daughter branches. It is quite evident that the reconstructed language bears morphological traces of a semantic-based system, similar to active-stative systems, as has been suggested by several scholars (Bauer 2000). But does it mean that Proto-Indo-European was an active language? Probably not. This concerns the question of stability of systems in general versus language-internal variation in tendencies to other systems. Indo-European alignment took three pathways of change, towards ergativity in the South-East, nautral marking in the West, and a preservation of the ancient system in between (roughly). What is the areal pressure component here, and what changes are dependent on internal procedures in languages, and what is the role of the residual morphology? These are questions that remain to be answered. 

McCone, Kim (1987), The early Irish verb (Kildare: Maynooth). 
Bauer, Brigitte (2000), Archaic syntax in Indo-European : the spread of transitivity in Latin and French (Trends in linguistics. Studies and monographs, 99-0115958-X ; 125; Berlin: Mouton de Gruyter).