Rit (Vísindafélag Íslendinga) - 01.06.1970, Side 93

9i
from another, naturally and inevitably leads to the notion
of functional load as a measure of the capacity of phonemes
to assume the distinctive function. And this notion, in turn,
once it is conceived of and given even a vague definition, is
bound to be applied to problems of diachronic phonology.
In this matter the central thesis is that, all other things being
equal, a distinctive opposition which has a high functional
load, and is therefore useful for maintaining mutual under-
standing, serves the purposes of communication better, and
ís therefore more likely to be preserved, than one which does
not (see, especially, Martinet 1955:54-59).
However, several difficulties are inherent in this notion.
Ffrst, it can be applied to the phonological opposition or to
the distinctive feature. (In English, for instance, only a few
minimal pairs are distinguished by the opposition þ: ð, whereas
the distinctive feature involved is a central constituent of the
English consonant system.) Second, there is the question
whether, in historical phonology, this notion can serve to
explain why a change, e.g., a merger, does or does not take
place, why it takes place in one language at one particular
htne, and not in another language at another time; or whether
tt should only be made to serve to elucidate the less ambitious
question of how, or in what direction, a change proceeds, if
tt takes place at all. And thirdly, there is the question whether,
m its application, this notion should be restricted to the counting
°f minimal pairs, or whether it should be related to, or even
considered to be simply an aspect of, the more general notion
of relative FREquENCY of occurrence, lexical and/or tex-
tual.
In practice, the most serious obstacle is the difficulty inherent
ln a precise quantification of this notion. To the best of my
knowledge,theonly attempt at establishing a strictlynumerical
measure of functional load as a basis for the analysis of sound
change is by King 1967 (a-b). The formal definition of the
functional load, L, of the opposition xt: Xj is given by the equa-
tion (King 1967 (b) 12-7):