Complexity Theory
What I choose to call Complexity Theory (CT), following Larsen-Freeman (2011), is closely related to what others in SLA call Dynamic Systems Theory (e.g. van Geert 2008), Complex Systems Theory, and Chaos Theory. The approach traces its roots to theoretical developments in the natural sciences, where its general goal has been to describe and explain change in complex systems (including language). Its first application to second language acquisition is usually credited to Larsen-Freeman (1997).
The key question in SLA which CT and related theories address has been viewed from a linguistic perspective for more than fifty years, as discussed in Chapter 3: What accounts for the nature and order of language development? As we have already seen, this has also been a key question as viewed from a psychological perspective. CT differs fundamentally from most linguistic approaches in denying that any innate mental faculty for language is required in an account of either first or second language acquisition. In this important respect it agrees with common views in psychology that learning is essentially the same process in any domain (not just language). CT also differs from many psychological perspectives, however, in integrating considerations of social and contextual factors along with cognitive ones in attempting to describe and explain the processes of SLA.
A basic concept in Complexity Theory as it applies to SLA is that all languages, and varieties of language, are complex systems with interconnected components and stages of learner language. Saying that a complex system has interconnected components means that levels of language like phonology, vocabulary, and discourse are interdependent in their development. In the process of development, the different components become more orderly, more structured or organized, over time. “Only by adopting an integrative dynamic framework will we understand how they come about” (Ellis 2008 :233).
The dynamic process thus accounts for the formation of patterns in the development of both first and second language acquisition, as well as all other complex systems in nature. This is an important departure from the claims of UG and even many functional views of grammar that basic rules and constraints of grammar are uniquely hard-wired in the brain. According to Complexity Theory, “these regularities are not rule-driven; there are no mechanisms for such top-down governance. Instead, they emerge from the dynamics of language usage” (ibid.).
In a further departure from most linguistic as well as prior psychological perspectives, descriptions and explanations of the dynamic processes of language change and development need to take into account the variable effects of communicative functions and opportunities, the structural relationships of L1 and L2, the intentions and acts of learners and others, and a host of other internal and external factors. (For a comprehensive and in-depth overview of dynamic aspects of SLA, see de Bot, Lowie, and Verspoor 2005.)
While this holistic view of SLA is appealing to many of us, it presents some problems for researchers who need to control variables in order to predict outcomes in different learning circumstances. The results of research from this perspective so far are yielding some interesting insights into language development processes and experiences, however, and have considerable promise for enlightening some of our teaching practices.
