Workshop on Complexity in Language – Day 2 (report)

I could not follow the whole second day of the Workshop on Complexity in Language (see previous post), but here is what I heard in the morning.

Salikoko Mufwene talked about the emergence of complexity, which he sees as a self-organization process : we don’t plan the way we are going to speak.

He adopts a relativistic perspective speaking of a multi-agent system and asking if the agents are really agentive or if there are triggers of particular behaviors. He likes to consider language as a technology that evolved. At the end of the talk he also tackled the notion of communal complexity and communal patterns used by speakers (also known as norms).

Luc Steels explained his understanding of language complexity and how he simulates communication with robots. He thinks there is an alternative to the evolutionary framework: according to him grammar is functional and not superficial and complexity has grown step by step in a cultural evolution rather than a biological.

His perception of self-organization bases most notably on alignment, structural coupling and linguistic selection. That’s what he builds models for by letting robots find common words to describe a situation (for example the fact that a given ...

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Workshop on Complexity in Language - Day 1 (report)

I attended yesterday the first day of a workshop organized by Salikoko Mufwene and held at the ENS Lyon. This “Workshop on Complexity in Language: Developmental and Evolutionary Perspectives” lasts two days: HTML version of the program.

Here is my personal report on what I heard during the first day and on what I found interesting.

Complexity and complexity science

First of all, William S.-Y. Wang referred to Herbert Simon and Melanie Mitchell in particular to define complexity, two approaches that I described on this blog.

Tom Schoenemann talked about the increasing richness, subtlety and complexity of hominin conceptual understanding which created a need for syntax and grammar as characteristics resulting from it. In the course of history brain areas appear less directly connected, they process information more independently. What he calls “conceptual complexity” bases on the idea of “grounded cognition” developed by Lawrence W. Barsalou.

Barbara L. Davis said of the complexity science that it was another paradigm. Indeed, most of the debate took place on an abstract level, with many different (and not really compatible) notions of language and complexity. William Croft for instance said the whole context of language needed to be taken into account, and ...

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Simon, Gell-Mann and Lloyd on complex systems

Definition

Herbert A. Simon is one of the first who tried to formalize the notion of a complex system: H. A. Simon, “The Architecture of Complexity”, Proceedings of the American Philosophical Society*, vol. 106, iss. 6, pp. 467-482, 1962.

First of all, here is how he defines it:

« Roughly, by a complex system I mean one made up of a large number of parts that interact in a nonsimple way. In such systems, the whole is more than the sum of the parts, not in an ultimate, metaphysical sense, but in the important pragmatic sense that, given the properties of the parts and the laws of their interaction, it is not a trivial matter to infer the properties of the whole. » p. 467-468

According to Simon the idea of hierarchy (and therefore of architecture) is preponderant.

« By a hierarchic system, or hierarchy, I mean a system that is composed of interrelated subsystems, each of the latter being, in turn, hierarchic in structure until we reach some lowest level of elementary subsystem. » p.468

Nowadays this definition can be considered as a keystone of complex systems theory. To find the architecture, the dependencies between the subsystems, how they interact and interface ...

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Melanie Mitchell: defining and measuring complexity

I just read with peculiar attention the seventh chapter of Complexity: A Guided Tour, by Melanie Mitchell (Defining and measuring complexity, pages 94 to 111). She works with the Santa Fe Institute which is a major institution regarding research on complex systems. She gives a convincing outlook of this field. Still, I did not read anything on the question of language as a complex adaptive system, although there are researchers who focus on this topic (e.g. in Santa Fe).

According to her, there are different sciences of complexity with different notions of what complexity means. The notion of complexity is itself complex. She chooses to refer to three questions coined by Seth Lloyd in 2001 to approach the complexity of a system:

  1. How hard is it to describe ?
  2. How hard is it to create ?
  3. What is its degree of organization ?

Then she details a few definitions which can be seen as sides of the problem. Beginning with a selection from a larger list by Seth Lloyd, she tries to explain where or if these approaches are used. Thus, according to her, these are possible definitions of complexity:

  • Size
  • Entropy
  • Algorithmic information content – Murray Gell-Mann speaks of « effective complexity »
  • Logical ...
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