Seite 4: Lexicons through language games

We now turn to the lexicon. As discussed in other papers , evolutionary language games can be defined that lead to the formation of a lexicon. In each game, there is a speaker and a hearer and a set of objects making up a context. The speaker identifies one object (the topic), for example by pointing. Both then find a feature set discriminating the topic with respect to the other objects in the context by playing discrimination games.

The speaker attempts to code this feature set into language by using words in a lexicon that relate words to meanings. The hearer decodes the resulting expression using his lexicon and the game succeeds if the distinctive feature set decoded by the hearer matches with the expected distinctive feature set. When the game fails, the speaker or the hearer change their lexicon. For example, if the speaker does not have a word yet for the distinctive feature set that he wants to express, he may create a new word and add a new association to his lexicon; if the feature set decoded by the hearer is more general than the one expected, then the hearer can refine his associations between words and meanings, etc. There is additional complexity because one word may have multiple meanings and one meaning may be expressed by multiple (competing) words.

Obviously many variants of such language games can be developed, including games where the feedback of success comes from the world. For example, when one agent asks another agent for an object using a linguistic expression, success occurs when the agent gets the object he wants.