It is now widely accepted that many organisms (including humans) don’t just react to the world using behavioral reflexes, but also, at times, decide what to do by relying on mental representations. More specifically, the behavior of many organisms is not simply triggered by a perception of the state of their environment, but inferred using higher-level mental states downstream from their perceptual states. What is far less clear is why this is the case: what benefits does representational decision making bring to an organism, and what implications do these benefits have for the exact role that ... More

It is now widely accepted that many organisms (including humans) don’t just react to the world using behavioral reflexes, but also, at times, decide what to do by relying on mental representations. More specifically, the behavior of many organisms is not simply triggered by a perception of the state of their environment, but inferred using higher-level mental states downstream from their perceptual states. What is far less clear is why this is the case: what benefits does representational decision making bring to an organism, and what implications do these benefits have for the exact role that mental representations play in an organism’s decision making machinery? In my book, I provide answers to these questions. Specifically, I defend a cognitive-efficiency-based account of the evolution of mental representations, according to which a key driver of the evolution of representational decision making is the fact that mental representations can enable an organism to save a number of cognitive resources and to adjust more easily to changed environments. I then apply this account to a number of open questions in different sciences, including: when should we expect cognition to essentially involve parts of the environment? When should we expect decision making to rely on simple, satisficing heuristics? When should we expect organisms to be altruistically motivated to help others? Along the way, I also respond to concerns about the plausibility of evolutionary psychological projects more generally.