In the linguistic literature much is made, both implicitly and explicitly, of metalinguistic abilities but little is seen on the role of individual differences. The role of individual differences in ambiguity detection and resolution is discussed here as an example of the range of individual variation in shared abilities of the metalinguistic type.

It is not the case that all reader/hearers of the language possess the same linguistic abilities with respect to metalinguistic tasks. From a theoretical point of view, linguists have typically assumed it was the case and necessarily so for postulating an ideal competence grammar. But in doing so we have often come to assume that such basic metatheory considerations show up reliably and uniformly even in performance tasks. There is a large and growing body of evidence to remind us that this is not so. Certainly, it holds true neither in the areas of paraphrase nor in ambiguity detection and resolution, two of the more basic metatheoretical premises, and it may not be so in other areas of language either. Very simply, apparently shared linguistic abilities operate on the same type of a graded continuum scale that cognitive abilities of a more general sort do. Having benefited from the postulation of abstract mental structures for ideal speaker/hearers, we are once again recognizing the importance of individual differences in defining the nature of psycholinguistic tasks, as well as the nature of language abilities.