摘要：The established descriptions of information structure assume that the basic cognitive unit is a categorization, and that the basic semantic structure is a predication. Descriptions based on these assumptions, however, cannot provide an adequate analysis of certain types of utterances that form a part of activities. The article presents a solution to this problem based on Wittgenstein’s private language argument and the concept of information in Gibson's theory of affordances. The basic cognitive assumption is that performers of activities attend to variations in the environment, for example visibility, and perceive the states of variations (e.g., 3000 feet). A state is defined as a local, temporary occurrence of a stimulus configuration that specifies an affordance. The basic pragmatic assumption, then, is that performers of activities share the states of variations by means of utterances. This ecological-pragmatic assumption allows for a rethinking of the usefulness of the reference-predicate distinction and bring forward different dimensions of informational analysis of utterances. It is claimed that an informative and accurate analysis of utterances that form a part of activities relies two distinctions: a distinction between a convention based regulation of attention and a convention based specification of an affordance, and a distinction between sharing information and nesting information
