Nomina (ctd.)
Contrastive accent and secondary full grades
Substantives tend to be distinguished from related adjectives by means
of contrastive accent. The phenomenon can be illustrated with such pairs
as *bHór-o-s 'load, burden' : *bHor-ó- 'carrying', both from the root
*bHer- 'carry'). Note that in this case we are not dealing with
straightforward substantivisation -- there is a diathetic contrast
between the agentive meaning of the adjective and the
passive/resultative meaning of the noun ('something carried'); agent
nouns like *bHor-ó-s 'carrier' are not distinguished from adjectives.
Feminine abstracts are accented on the thematic element (*bHor-á-h2)
irrespective of whether the focus is on an activity ('act of carrying')
or the corresponding state ('being carried, motion').
The unstressed o-vocalism of the *bHor-ó-/*bHor-áh2- type has been
exhaustively treated by Jens Rasmussen, who was kind enough to present a
convenient summary here:
http://groups.yahoo.com/group/cybalist/message/30940
The tendency to use contrastive accent must have operated throughout the
history of PIE and into the early "dialectal" stages. Several
chronological layers can be discerned. To begin with the oldest, there
was a time when accent retraction to a formerly unaccented syllable
caused the appearance of a full vowel there, while the syllable that had
lost its accent was phonetically reduced. In particular, thematic *-o-
became *-u-. Let us imagine a root like *kret- (a real example, with the
approximate meaning of 'strengthen'. The addition of anaccented
adjectival suffix like *-ró- forms a verbal adjective: *krt-ró-
'strengthened', dissimilated to *krt-ó-. Accent retraction produces the
noun *krét-u-s 'being strong, power'. Note that the full vowel is
inserted where it belongs, which means that at that stage speakers were
aware of the underlying vocalism of the root: perhaps the actual
realisation of the weak grade at that time was *kr&t-, with an
appreciable (even if reduced) vowel. Later an adjective was formed from
*krét-u- by another application of the principle of contrastive accent,
this time yielding *kr.t-ú- (at a time when a stressed zero grade was
already possible, but loss of accent still caused vowel reduction).
More recently, a similar scenario was re-enacted. From the root noun
*djeu- 'the bright sky, heaven' it's possible to derive thematic *diw-ó-
'belonging to heaven, celestial', and then (on the analogy of nouns like
*krétu-) *déiw-o-s 'celestial being, deity'. Here the vowel was inserted
in the _wrong_ place, since the weak grade *diw-, with the unstressed
vowel reduced to zero, had become ambiguous. PIE speakers had the same
difficulty with other *CREC roots, which often developed secondary full
grades of the form *CERC. Note also that the post-tonic reduction of the
thematic vowel was no longer obligatory at the stage in question.
However, qualitative ablaut was still productive, so when a new
adjective of belonging was formed from *déiw-o-s, it took the form of
*[deiwo-]-ó- --> *diwi-ó- 'belonging to the gods, divine, heavenly'
(Skt. divyá-, Gk. di^os < *diwios). Still later, another contrastive
accent shift produced another adjective without causing any segmental
effects: *deiw-ó- 'divine'.
The most recent layer contains cases like *mr.-tó- 'dead' vs. *mr.'-to-
'murder (PGmc. *murDa-) or RV krs.n.á- 'black' vs. kr.'s.n.a-
'blackness; a kind of dark antelope' or Kr's.n.a- (the god).
Piotr