The Thomas Theorem is a special way of thinking about how people act and react to certain situations. It was named after American sociologist William Isaac Thomas who said: “If men define situations as real, they are real in their consequences.” In other words, this means that if people believe something, they will act and react as if it were true and then the results can be real and affect their lives. For example, if a person believes that all their friends don’t like them, they might start to act in a way that turns people away, until pretty soon all their friends do start to avoid them. The Thomas Theorem helps us to understand why things like this can happen, and how our beliefs can create our own reality.