Agent-Based Models of Language Evolution

Luc Steels

Institute for Advanced Studies, Barcelona and Sony Computer Science Laboratory, Paris

Thursday, March 29, 2012
11:00am

The historical evolution of human languages is fascinating. Few people know that articles, like "the," arose only fairly late in the evolution of Germanic languages (namely in late old English or old Dutch), that there were no nominal phrases in proto-Indo-European because these only formed gradually by the incorporation of free modifiers at the sentence level into the nominal constituent, that Germanic languages (and many other language families) had originally a brightness-based color system with a switch to a hue-based systems only in late medieval times, and so on. The past few years, interest in historical linguistics has increased significantly. This is partly due to the growing availability of corpus data and techniques from complex systems science that allow the detection and analysis of trends in large amounts of data. It has given us a much better idea of what exactly has happened but observation alone is not going to tell us why and by what causal mechanisms cultural language change takes place. We should try to go beyond historical linguistics to develop a true theory of "evolutionary linguistics," similar in explanatory power to evolutionary biology.

Agent-based modeling appears to be a very powerful framework to achieve this. Agent-based models of language evolution introduce a population of agents endowed with basic linguistic abilities for conceptualization, production, parsing, and interpretation. Agents are also endowed with mechanisms for learning language and for expanding their conceptual and linguistic inventory to deal with new challenges or optimize their communication systems to diminish cognitive effort. From timid beginnings, agent-based models of evolutionary linguistics are flourishing with case studies for the origins of color vocabulary, spatial language, action words, proper names, tense, case grammar, determiners, a.o. (Steels, 2011;2012). This talk gives an overview of what could already be achieved and then discusses more recent experiments that try to bring agent-based models in closer contact with actual data from historical linguistics.

Steels, L. (2011) The cultural modeling of language evolution. Physics of Life Reviews. 8(4) 330-356.
Steels, L. (2012) (ed.) Experiments in Cultural Language Evolution. John Benjamins Pub. Amsterdam