From the moment that history started to be recorded until now, we have tried to understand why humans behave the way they do. We want to be able to describe what people do, as well as how and why they do it. There are various societies that have looked into quantifying and describing these observations, such as the Hindus, the Greeks, the Romans, Native Americans and Africans.
Ancient civilizations created models to described behavior that are still being used today. In fact, some of these models are being relied on, such as the “Humours” description of Hippocrates or the body fluids analogy of Galen. Other methods, such as astrology and numerology, are perhaps not as popular anymore today, but they are still being followed by some.