Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School

Imagine sitting down with a fortune-teller to find out your future. The fortune-teller can determine intimate details about your life and personality. As they talk to you about your future, you feel disarmed by their knowledge and wonder if their predictions may come true. What is really going on behind the crystal ball? How does the fortune-teller know so much about you? The answer is theory of mind. This term refers to people’s abilities to recognize and comprehend the mental states of others. Many people—such as fortune-tellers—capitalize on their ability to “read” other people and pinpoint their motivations. As the prefrontal cortex in children develops, so does their theory of mind. By the age of four, neurotypical children can pass the false-belief test. This experiment asks children to look inside a candy box filled with pennies. They are then asked what others might believe is inside the box. Younger children usually say pennies. They are unable to separate their own experiences from the experiences of others. However, by age four, most children can recognize that others would assume the box would be filled with candies because they have not looked inside. This means that they have begun to think beyond themselves. They consider others’ feelings and experiences and make choices based upon the wants and needs of others.

Theory of mind is called a “theory” because the assumptions people make about other’s experiences are based only on outward observations rather than empirical evidence of what others’ brains are doing. The term has philosophical roots, going as far back as 1641, when philosopher René Descartes published Meditations on First Philosophy in which he questions the mind and its relationship to the outside world. Medina claims that theory of mind can be divided into two parts. The first is the ability to understand rewards and punishments that affect the cognitive functioning of individuals other than oneself. The second is the ability to understand that one’s own rewards and punishments may not align with or reflect the rewards and punishments of others. Theory of mind is not empathy; understanding others with insight does not always translate to kindness or the preservation of others’ well-being. Sometimes people unwittingly utilize theory of mind to get what they want and to manipulate others for the benefit of their personal rewards and punishments.

Medina believes theory of mind skills are extremely important to maintain social relationships and therefore for the success and evolution of the human species. Adults practice theory of mind innately. In one study, participants were asked to count the number of dots on the wall of a room. The study showed that responses were slower when another person in the room claimed to see fewer dots than were present. This means the participants were likely unconsciously affected by their perceptions of what others were thinking. However, theory of mind is only a guess as to others’ perceptions. It is an imperfect attempt to understand what others are thinking. While many would suggest that the candy box is filled with candy, there might be those who believe it to be filled with pennies. Theory of mind cannot conclusively predict what others are thinking.

Theory of mind is important for understanding the field of neuroscience and Medina’s work. Neuroscience aims to examine the theory, based on intuition and assumption, and test it empirically. Neuroscientists apply rigorous testing to the beliefs and suppositions of how the brain works. Medina’s Brain Rules clears away the fog and provides definitive rules to what human brains are doing; it translates theory of mind into something tangible and testable.