What is Theory of Mind?

The term “Theory of Mind” has been used interchangeably with a number of related concepts (mentalizing, mirroring, mindreading, to name a few), operationalized in a variety of ways (such as the ability to attribute false beliefs), and investigated at multiple levels (philosophical, psychological, and neurobiological). This feature, together with the explosion of research on the topic, have resulted in a rather fuzzy picture regarding how best to define Theory of Mind, how to relate it to the other terms, and how to study it. I will provide an overview aimed at isolating a few, clear paths forward; emphasize distinctions that I believe we will need to keep in mind; and provide a glimpse of current and future experiments using tools from cognitive neuroscience. I will close by speculating on what aspects of mindreading might be unique to humans: namely, the ability volitionally to use our conscious experience to explore viewpoints (in space, time, or personhood) that are decoupled from what the senses directly deliver.