Abstract

A widespread assumption in experimental comparative cognition is that, barring compelling evidence to the contrary, the default hypothesis should postulate the simplest cognitive ontology consistent with the animal’s behavior. I call this assumption the principle of cognitive simplicity . In this essay, I show that PoCS is pervasive but unjustified: a blanket preference for the simplest cognitive ontology is not justified by any of the available arguments. Moreover, without a clear sense of how cognitive ontologies are to be carved up at the joints—and which tools are appropriate for the job—PoCS rests on shaky conceptual ground