What is "high"? The development of reference points for "high" and "low".

Young children have been characterized as interpreting relative adjectives as if they were nominal or categorical terms. The categorical interpretation of relative terms, however, may be quite complex. Indeed, the mature understanding of relative terms would seem to include a complex system of reference points for the terms' categorical usages. In 5 experiments we examined the complexity of 3-5-year-old children's and adults' categorical interpretations. We specifically examined how reference points for the categorical interpretation of high and low are defined. The definition of reference points relative to the object judged, the vertical position of the observer, and the extent of vertical variation were assessed. 3 major developmental trends were observed: a trend from the application of the terms to only extreme values to their application to broader categories; a trend from nominal-like categories to ones defined flexibly relative to context (e.g., nature of object judged, and extent of vertical variation); and a trend from reference points functioning as focal points to their operating as directional category boundaries. In brief, the results suggest that the categorical usage of relative terms involves a rich and intricate knowledge system and that it takes children considerable time to acquire and organize the relevant pieces of knowledge.