The topic of this book is mental representation, a theoretical concept that lies at the core of cognitive science. Together with the idea that thinking is analogous to computational processing, this concept is responsible for the 'cognitive turn' in the sciences of the mind and brain since the 1950s. Conceiving of cognitive processes (such as perception, reasoning, and motor control) as consisting of the manipulation of contentful vehicles that represent the world has led to tremendous empirical advancements in our explanations of behaviour. Perhaps the most famous discovery that explains behavior by appealing to the notion of mental representations was the discovery of 'place' cells that underlie spatial navigation and positioning, which earned researchers John O'Keefe, May-Britt Moser, and Edvard I. Moser a joint Nobel Prize in 2014. And yet, despite the empirical importance of the concept, there is no agreed definition or theoretical understanding of mental representation. This
