ABSTRACT
This chapter sets out in some detail the relationship between these two disciplines psychology and linguistics. Everyone who knows a language possesses certain skills. These include the power to produce and understand sentences, and the ability to decide whether or not a sentence is grammatical. It is rather difficult, however, to say exactly what is meant by the assertion that a person knows a language. A complete set of rules is a grammar of the language. In one sense this provides an answer to the question of what the speaker knows: it is the grammar. However, this can prove to be a rather unmanageable idea. In the case of the language user, the grammar provides a similar way of imposing order on a set of observations. However, there are many ways of doing this and we must not fall into the error of treating the rule system as equivalent to a set of psychological processes.
