The present book is a testimony of the great advances that have been made in the study of humanness and dehumanization in psychology, as well as the vitality of this field. The chapters are all original, and each of them provides new ideas. This chapter summarizes some of the fundamentals on humanness and dehumanization, distilling what we see as the central themes and more important avenues for future research that emerge from this endeavor.

We are all condemned to the impossibility of gaining full access to other people’s minds. This premise is the starting point of Waytz, Schroeder, and Epley (Chapter 4). People can only infer the existence and the inside of other minds from their own mind, meaning that individuals rely on indirect information that is prone to different types of systematic biases. Waytz and colleagues (Chapter 4) explain that these biases often lead to seeing other people as being less mindful. Their minds are seen as less intense, less causally impactful, and less objective than one’s own, a phenomenon that they coin the lesser minds problem. In many ways, the “lesser minds” approach is a modern version of the cognitive miser. Like in the latter approach, people make mistakes particularly when they are not motivated and do not possess enough cognitive capacities (Fiske & Taylor, 1984).