Evolutionary Linguistic Theory - Volume 3, Issue 1, 2021

Structurally, cognitive and biological evolution are highly similar. Random variation and constant but blind selection drive evolution within biology as well as within cognition. However, evolution of cognitive programs, and in particular of grammar systems, is not a subclass of biological evolution but a domain of its own. The abstract evolutionary principles, however, are akin in cognitive and biological evolution. In other words, insights gained in the biological domain can be cautiously applied to the cognitive domain. This paper claims that the cognitively encapsulated, i.e. consciously inaccessible, aspects of grammars as cognitively represented systems, that is, the procedural and structural parts of grammars, are subject to, and results of, Darwinian evolution, applying to a domain-specific cognitive program. Other, consciously accessible aspects of language do not fall under Darwinian evolutionary principles, but are mostly instances of social changes.

This paper discusses Hubert Haider’s target-article “Grammar change: A case of Darwinian cognitive evolution”. I show why such an article is fascinating (and unconventional), although I will mainly concentrate on several disagreements with Haider and will suggest alternative views to those contended by this scholar. My discussion will highlight five main issues: (1) Haider assumes a purely Neo-Darwinian (i.e. genocentric) view of evolution and inheritance, lacking a more pluralistic approach; (2) Haider rejects the idea of language as a biological phenomenon, while at the same time he seems to assume several characteristics related to a biologically seated trait; (3) as opposed to Haider’s suggestion, the computational system does not need to be language-specific; (4) Haider’s divide between the procedural and declarative components of grammar is perhaps too strict regarding (grammatical) change; and (5) Haider considers that there is no scientific way of deciding the question of language origins and evolution and that complex grammars are too recent. However, I show that a language-like computational power (and perhaps complex grammars) already existed many thousands of years ago.

Haider’s target paper presents a fresh and inspiring look at the nature of grammar change. The overall impression of his approach is very convincing, especially his insistence on the point that language was not selected for communication – hence it is no adaptation to communicative use. Nevertheless, I think three topics are in need of further discussion and elaboration. First, I will discuss the question whether Haider’s conception of Darwinian selection covers all aspects of grammar change. Second, I will consider the question of whether an approach that dispenses with UG (as Haider’s does) can explain why grammars are the way they are. Third, I will question Haider’s equation of grammar with the genotype and of speech with the phenotype and develop an alternative and more appropriate proposal where, among others, speech corresponds to behavior.

This commentary discusses some aspects of Haider’s model of grammar change that are problematic from the perspective of usage-based approaches to language change. These aspects include (i) the postulated equivalence between intentionality and teleology, (ii) the metaphorical nature of Darwinism when applied to other domains, and (iii) the nature of explanations of language change. With respect to (i), it is argued that equating intentionality with teleology disregards the fact that innovation in grammar is not unprincipled like in genes. With respect to (ii), the question is whether a comparison between as different concepts as human behaviors/brains and genes/populations can be considered as more than a metaphor (however powerful). Finally, with respect to (iii), a number of diachronic-typological studies are discussed that concur to suggest that variation in speakers’ verbal productions is largely adaptive, and therefore selection operates on a skewed pool of variants in which non-adaptive/dysfunctional variants are a minority (if any).

Approaching language change within a Darwinian framework constitutes a long-standing tradition within the literature of diachronic linguistics. However, many publications remain vague, omitting conceptual details or missing necessary terminology. For example, phylogenetic trees of language families are regularly compared to biological speciation, but definitions on mechanisms of inheritance, i.e. how linguistic information is transferred between individuals and cohorts, or on the linguistic correlates to genotype and phenotype are often missing or lacking. In light of this, Haider’s attempts to develop this approach into a theoretically more precise position, closely mirroring principles of Darwinian natural selection in the dimension of diachronic grammatical change, but contrasting this with non-Darwinian lexical change. He draws a comparison to viral replication, essentially positing that grammar variants act as mental viruses, competing for replication in new hosts, i.e. children during critical periods of language acquisition. Haider proposes that in light of this competition for replication, the unconscious fixation of an individual’s grammar leads to diachronic grammatical change largely mirroring Darwinian natural selection. Despite the intuitive appeal this mode of reasoning may feature, the following response paper identifies and discusses a suit of shortcomings to this conceptualization. Some problems arise from underspecified theoretical notions, others due to the incomplete or inaccurate adoption of biological principles, and yet more through a partial incompatibility with empirical data. These criticisms do not amount to a dismissal of the Darwinian framework Haider is following, but to a rejection of Haider’s current position. Albeit it remains unclear if a truly Darwinian approach to language change can be reached, suggestions on how Haider’s theoretical notions could be further developed are made and pertinent efforts may ultimately lead to a productive theory.