A good understanding of the nature of a property requires knowing whether that property is relational or intrinsic. Gabriel Segal's concern is whether certain psychological properties—specifically, those that make up what might be called the "cognitive content" of psychological states—are relational or intrinsic. He claims that content supervenes on microstructure, that is, if two beings are identical with respect to their microstructural properties, then they must be identical with respect to their cognitive contents.
Current textbooks in formal semantics are all versions of, or introductions to, the same paradigm in semantic theory: Montague Grammar. Knowledge of Meaning is based on different assumptions and a different history. It provides the only introduction to truth- theoretic semantics for natural languages, fully integrating semantic theory into the modern Chomskyan program in linguistic theory and connecting linguistic semantics to research elsewhere in cognitive psychology and philosophy.