3 Fallacy of a single origin
Human language is a complex system which combines several independent
capacities (modules), most notably the Merge-based computational system plus
the CI and SM systems with which it interfaces. This modular architecture is
what guarantees the evolvability of language; in general, non-modular monolithic
systems hardly evolve. Accordingly, the problem of language evolution needs to
be decomposed into two distinct problems: (A) How did each of these modules
evolve? What are their precursors? (B) How did these modules get integrated
into the complex system we call language? Problem (A) can be loosely called
the origin problem; problem (B) the interface problem (Figure 9.3).
In this perspective, it no longer makes sense to simply ask what human lan-
guage evolved from, but we need to ask which components of language evolved
from what kind of preexisting capacities. Any statement of the form Language
evolved from X (X being a single trait, be it gestures, speech, songs, music or
whatever else) is doomed to be false, and this wrong idea that language must
have evolved from a single preexisting capacity well represents the fallacy of a
single origin.
M. Corballis once stated that “language evolved, not from the vocal calls of
our primate ancestors, but rather from their manual and facial gestures” (Corbal lis
2002: ix). Why not both vocal calls and gestures, each responsible for different
aspects of language? What is called for is again a pluralistic view, in which every
candidate must be considered as a possible precursor of a particular module,
not of the whole language suite, without necessarily precluding the possibility
that a single module had a multiple precursor.
Ve r y f a m o u s l y, H a u s e r e t a l. ( 2 0 0 2 ) p r o p o s e d t h e d i c h o t o m y b e t w e e n a f a c u l t y
of language in the narrow sense (FLN) and a faculty of language in the broad
sense (FLB), FLN being the component of language which is both species-
specific and domain-specific, while FLB includes FLN and every other component
which is not specific in one way or another. They further suggested that only
recursion, which can be safely equated with Merge in the present discussion
(Hauser et al. did not refer to Merge per se at all), belongs to FLN, whereas
the CI and SM systems do not. In other words, these latter two systems may
easily find their evolutionary precursors in the realm of non-human cognition,
including primate conceptual systems and phonological syntax of songbirds.
Figure 9.3 Two major problems of language evolution. The vertical arrows represent
the origin problem; the horizontal arrows the interface problem.
Fallacies in evolutionary linguistics 145