Pinker & Bloom and Hauser-Chomsky-Fitch

Thursday, February 7, 2008 Language Evolution II: Pinker & Bloom
If there is one paper you definitely should cite when writing about Language Evolution, it is the seminal article “Natural Language and Natural Selection” (the prefinal draft can be found here) by Steven Pinker and Paul Bloom, which offers a good starting point for giving an overview of discussions about language evolution (Christiansen/Kirby 2003b: 15) because they review the contemporary theoretical paradigms of the field – like that of Chomsky, which I described in my last post – and then argue against them. They refute the view that language is wholly incompatible with Darwinian theory as well as the theory that language could be an exaptation (Pinker/Bloom 1990: 707).

In their opinion, language shows signs of “adaptive complexity”, the term describing “any system composed of many interacting parts where the details of the parts' structure and arrangement suggest design to fulfill some function” (Pinker/Bloom 1990: 709). Natural selection, that is the hypothesis that “the differential reproductive success associated with heritable variation is the primary organizing force in the evolution of organisms”, is the only scientific explanation for the development of such complexity (Pinker/Bloom 1990: 708), which could only have evolved gradually (Pinker/Bloom 1990: 711).The function language evolved for was the communication of complex propositions. As the authors themselves point out, their paper does not so much present a new theory of language evolution as set the methodological framework for a new scientific research program (Pinker/Bloom 1990: 726f.)... Posted by Michael at 10:22 Labels: Adaptation, Language Evolution

Monday, February 11, 2008 Language Evolution III: Hauser, Chomsky, Fitch 2002
When Hauser, known for his strong continuist position, and Chomsky, known as a strong discontinuist, collaborated on the programmatic paper “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” together with W. Tecumseh Fitch, it was, as Derek Bickerton states, “almost as if Ariel Sharon and Yasser Arafat had coauthored a position paper on the Middle East” (Bickerton 2007: 519).

Just as the 1990 paper by Pinker and Bloom, this paper reviews other hypotheses about language evolution and then, synthesizing a massive amount of comparative data, proposes a new research agenda. It gives a good impression of the state of the discussion in the first decade of the twenty-first century, especially when taking into account the heated debate that revolved around this research program between these authors and Pinker and Jackendoff, which I will describe in my next post.

HCF distinguish between the faculty of language in the broad sense (FLB) and the faculty of language in the narrow sense (FLN). FLB consists of a “sensory-motor” system, including phonetics and phonology, as well as a “conceptual-intentional” system, including semantics and pragmatics (Fitch/Hauser/Chomsky 2005: 182), and may be other systems (Hauser/Chomsky/Fitch 2002: 1571f.). It
“includes all of the many mechanisms involved in speech and language, regardless of their overlap with other cognitive domains or with other species”. FLB also comprises FLN, a subset which contains the aspects of language that are responsible for the fact that humans are the only species capable of language, and thereby should be a unique aspect of language as well as humanness (Fitch/Hauser/Chomsky 2005: 180f.).

Thus, research into the evolution of language is divided into three different areas of inquiry, according to the computational systems that comprise the faculty of language, as well as a fourth that is concerned with the interfaces between them. For each component, it has to be assessed whether the capacity is a uniquely human trait or if it is shared with other species, second, whether it developed gradual or saltational, and third, if it was an adaptation for communication or an exaptation of some other computational function (Hauser/Chomsky/ Fitch 2002: 1571).

HCF present three hypotheses which display the opinions of various scholars, with the third as their own viewpoint. The first hypothesis assumes that the faculty of language is strictly homologous to communication components of animals. The second hypothesis, which for example is stated by Pinker and Bloom, is that the faculty of language is a derived, uniquely human and highly complex adaptation for language “and many of its core components can be viewed as individual traits that have been subjected to selection and perfected in recent human evolutionary history”, and can be accounted for by natural selection (Hauser/Chomsky/Fitch 2002: 1572). HFC take a different stand. Their hypothesis is that only the core component of recursion, that is narrow syntax and the mappings to interfaces of FLB, “is recently evolved and unique to our species” (Hauser/Chomsky/Fitch 2002: 1573).

Furthermore, they argue that “FLN may have evolved for reasons other than language” (Hauser/Chomsky/Fitch 2002: 1571), and that recursion could be an exaptation that originally “evolved to solve other computational problems such as navigation, number quantification, or social relationships” (Hauser/Chomsky/Fitch 2002: 1578). FHC emphasize that their hypothesis needs further empirical research (Hauser/Chomsky/Fitch 2002: 1578) but is superior to many other theories because it presents itself in a tentative and testable manner (Hauser/Chomsky/Fitch 2002: 1572). They advocate that inquiry into problems of language evolution is in need of massive multidisciplinary efforts and much more sampling of comparative data to assess whether a trait evolved specifically for human language or is homologous to animal computations, “although it may be part of the language faculty and play an intimate role in language processing” (Hauser/Chomsky/Fitch 2002: 1572).

One thing I have to say about the article is that, although I wrote that it offers a good starting point, it actually is pretty murky and unclear, and without reading their “Carifications and Implications” I probably wouldn’t have understood what the whole paper really was about. And I think that the description of the language faculty as “narrow syntax and the mappings to interfaces of FLB,” doesn’t really tell us much regarding explanatory adequacy or how the thing really is supposed to work.

Nevertheless, or maybe even because of this, their proposal caused quite a fuzz, both in the blogosphere (An excellent discussion by Carl Zimmer can be found here (Part I) and here (Part II) and in the form of other articles launched to attack or to enforce HCF’s theory. The most prominent attack probably came from Steven Pinker and their paper “The Faculty of Language: What’s special about it?” I will describe the debate between those two ‘teams’ in my next post.

P.S.: Over at the Language Evolution blog, you can find the second presentation in a series about "Major Language Evolution Papers", this time about a paper by Mesoudi et al. (2004), which discusses the cultural dynamics of evolutionary processes.

References: Bickerton, Derek 2007. “Language Evolution: A Brief Guide for Linguists.” In: Lingua 117, 510–526. Fitch, W. Tecumseh, Marc D. Hauser and Noam Chomsky 2005. “The Evolution of the Language Faculty: Clarifications and Implications.” In: Cognition 97, 179-210. Hauser, Marc D., Noam Chomsky and W. Tecumseh Fitch 2002. “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” In: Science 298, 1569-1579. Posted by Michael at 10:50 Labels: Language Evolution, Recursion