Definitions
Definitions are important because communication depends on shared meaning. When the source meaning of a word is studied, it becomes possible to trace the path that meaning has taken. The direction of our psychological evolution and development as a species can be traced through the origin of words. A good example of this can be observed through studying the origins of the word psychology.
Definition of Psychology
The word psychology means, "study of the soul"
ψυχή, psukhē, meaning "breath", "spirit", or "soul”
λογος -logos, translated as "study of" or "research”