The Roman philosopher and
physician Claudius Galen
formulated a concept of
personality types based on the
ancient Greek theory of humorism,
which attempted to explain the
workings of the human body.
The roots of humorism go back
to Empedocles, a
Greek philosopher who suggested
that different qualities of the four
basic elements—earth (cold and
dry), air (warm and wet), fire (warm
and dry), and water (cold and
wet)—could explain the existence of
all known substances. Hippocrates
, the “Father of