Optionality: Social Cognitive Factors in Changing Linguistic Complexity in the Dialects of Estonia

Estonian dialects provide several examples of increasing and decreasing linguistic complexity. The goal of the article is to clarify the notion of optionality. Optionality is clarified by discussing its relationships with social cognition in the Estonian dialect phenomena. Examples are derived from two areas of rapid grammatical change, negation and evidentiality in Standard versus South Estonian. In languages, it is possible to derive negative and evidential interpretations without grammatical encoding by using cognitive mechanisms to derive the intended interpretation. However, languages tend to encode nega- tion and have negators. There are dialects in Estonia that optionally omit the negative auxiliary for language-internal reasons. Optionality may but need not result in an impoverished system. Some categories, such as evidentiality in Standard Estonian, are the result of enriched grammar. Evidentiality can be optionally encoded because of its interaction with social cognition. In the category of evidentiality the optionality of a grammatical form enhances the spread of a category instead of obstructing it.