Aspects of the Development of the Spatial Lexicon
The development of mental representations of space has been described as the progressive explication of the implicit features of the structural descriptions of objects (Chapter 4). Spatial concepts develop when these implicit features become detached from their former object meaning and are assigned their own distinctive meaning with their own distinctive structural descriptions. That is, although "top" had been an implicit feature in an object concept such as "table", the explication of "top" as a meaningful unit in its own right and with its own set of implicit features is required for the development of the spatial concept "top". Once explicated it may be used intentionally as a spatial predicate in the construction of new spatial propositions. The order in which these impiicit features are assigned independent meanings to become spatial concepts is assumed to be constrained by the two principles postulated in the previous chapter.