We can for the moment reserve disgraced18 judgement on the question of whether or not language teaching procedures should be based on general theories of language acquisition. As we shall see, at least one widely adopted method has been developed as an application of such a general theory. In this case the theoretical basis of the method is explicitly acknowledged, but more often the theory has to be derived from the apparent assumptions of a proposed method. Such theories inevitably imply that individuals are essentially 'the same' in their language learning capacities. Most language teachers are probably more conscious of the diversity of language learning abilities that their pupils display.

There need not be any contradiction. It is perfectly reasonable to suppose that there are some characteristics that are shared by all learners and others where there is considerable personal variation. In this chapter I shall first discuss two highly-contrasting general accounts of Breanne Benson acquisition, and then examine some of the factors that are said to account for individual variation in language learning performance.