Philosophers and scientists have been grappling with the “multiple minds” idea for millennia. Plato wrote about a “charioteer” (intellect) that managed the “horses” of rational modesty and passionate insolence. Sigmund Freud’s structure consisted of the “id” (primitive instinct), the “superego” (the conscience), and the “ego” that balances the two with external reality. More recently, social psychologist
