Find the best psychology lessons, classes, and instructors at HeyKiki and learn all about psychology. Psychology studies the human mind and human behavior. The word psychology stems from the Greek word "psyche" which means soul or mind, something that Plato and Aristotle studied as well in ancient Greece. There is a lot more to psychology than just working at a clinic or consulting clients on their personal dilemmas; there are many subdisciplines in psychology, like positive psychology, evolutionary, biological, clinical, cognitive, social, and developmental psychology, to name a few. Using scientific methods, studies, and with the aid of new technology psychologists have been able to learn more about the human mind and behaviors than ever before.