Margolis — The Conceptual Mind El 19 All Concepts Are Ad Hoc Concepts

To explain how people think and communicate, cognitive scientists posit a repository of concepts, categories, and word meanings that are stable across time and shared across individuals. But if concepts are stable, how can people use them so flexibly? Here we explore a possible answer: maybe this stability is an illusion. Perhaps all concepts , categories, and word meanings (CC&Ms) are constructed ad hoc, each time we use them. On this proposal, which we call the ad hoc cognition (AHC) framework, all words are infinitely polysemous, all communication is " good enough, " and no idea is ever the same twice. The details of people's ad hoc CC&Ms are determined by the way retrieval cues (such as words) interact with the physical, social, and linguistic context. Commonalities across instantiations of CC&Ms yield some emergent stability and create the illusion of context-independent core properties. Here we argue that even the most stable-seeming CC&Ms are instantiated via the same processes as those that are more obviously ad hoc, and they vary (a) from one microsecond to the next within a given instantiation, (b) from one instantiation to the next within an individual , and (c) from person to person and group to group as a function of people's experiential history. If this is true, then a central goal of research on language and cognition should be to elucidate the fleeting, idiosyncratic neurocognitive representations that people actually use for thinking and communicating, rather than to discern the nature and origin of context-independent CC&Ms, which, we argue, only exist as theoretical abstractions. Thinking depends on brains, and brains are always changing ; therefore thoughts are always changing. Rather than trying to explain concepts, categories, and word meanings as things that we have in our minds, like entries in a mental dictionary or mental encyclopedia, it may be more fruitful to build theories of conceptualizing, categorizing, and constructing word meanings: things that we do with our minds.