In the preceding chapter, we looked at some of the properties of language strings. We examined the relations among morphemes that are available to carry information about the relations of concepts. We considered several lines of argument converging on the conclusion that language strings have an organization beyond their sequential structure. The organization is hierarchical, that is, organized at several different levels simultaneously, and the organization can be recursive, which allows parts of the organizing principle to be used over and over again.

The organization does not appear explicitly in language strings, but its existence can be inferred from the strings and how they are handled by language users. No contemporary account of the psychology of language or linguistics denies such organization (although a few may ignore it, e.g., Winokur, 1976).

The organization is the basis for the syntactic code that enables language strings to carry information about the relation of concepts. To understand a string, the language user must convert the sequence of morphemes (inflected lexemes plus function words) into something from which the idea may be extracted. When expressing an idea, the process is reversed. The cognitive operations involved can be described as the syntactic mechanism of the language user. A description of and a model for this mechanism are given in Chapter 5.

In this chapter we are going to study the contents of the second box in the flow chart of Figure 1.4: underlying conceptual structure.