Evolving Social Constraints on Individual Conceptual Representations
(with Peter Gärdenfors)
The paper deals with how constraints on conceptual representations evolve through processes of knowledge sharing. We describe pragmatic settings of referential communication and provide a model of how names, nouns and adjectives emerge through a process of abstraction. In situations of referential communication, the contrast class - the set that intended referents must be distinguished from - is important for determining the degree of specification of referential utterances. Two processing strategies involving contrast classes are proposed that are connected to the nominal and adjectival levels of abstraction. Certain cognitive representational skills are needed to be able to assess a contrast class in a communicative situation. We propose three communicative strategies that correspond to different assessments of the relevant contrast class.
Short note on the paper:
This paper is the most recent in the thesis, written in 1998 together with Peter Gärdenfors, and a shorter version was presented at the 2nd International Conference on the Evolution of Language, London, in April 1998. The present version has been submitted to the proceedings of that conference.
The paper deals with a form of micro-evolution in language: what happens with the individual's conceptual representation when it is shared in a language community. According to Freyd (1983), communication is most efficient if cognitive representations form a grid with discrete values on few dimensions. We start out from Freyd's results and show in what setting (referential communication) this applies, and what cognitive capabilities are needed for this form of conceptual evolution to work.
Several different areas are loosely connected to each other, but are united by the situation that is analyzed - the setting of referential communication. As an illustration, let us consider what is needed for "me" to ask "you" to fetch a red ball in the living room.
In the example above, the noun "ball" represents an abstraction that has evolved in communicative practices in socio-cultural contexts where a ball is something important for us to talk about. The abstraction is grounded in prelinguistic categorization and exploits our ability to perceive covarying properties. The existence of such a word "ball" apparently makes our communicative games more efficient.
The word "red" also builds upon a prelinguistic conceptual apparatus, but of a different kind from the nouns. Instead of focusing on a multitude of covarying dimensions, adjectives like "red" focus on single dimensions. We also need to be able to perceive red as a salient property, and furthermore it is necessary that the distinction between red and non-red objects is useful for us. (See Paper Four.)
The difference in level of abstraction also represents a difference in level of interaction. We interact with things on the level of nouns, i.e. with all its properties at a time, rather than with single dimensions.
All referential communication builds upon the possibility to distinguish the intended referent efficiently. The distinction must be as good as to assure communicative efficiency, but it is not necessary to distinguish for example color, size or weight of the ball in the living room if there is only one. On the other hand, the cognitive task of computing the level of specification may be so hard that it is easier to overspecify the reference.
A major concern for us in this kind of evolutionary study is to model the evolution of language as a process that develops gradually, with the communicative outcome always being assured, and with individuals of different stages of linguistic evolution being able to communicate with each other, so that it is not necessary to assume immediate shifts in whole populations.