The term “Psychology” consists of two Greek words — Psyche and Logos. The former means “soul” and the latter means “Science”. Psychology thus means science of soul. But the term “soul” cannot be easily explained and understood. This led to the meaning of psychology as the “science of mind”. This also raised a number of questions. What is mind? Where is mind? What it does? The answers to these questions are not clear and acceptable to all.

Such confusion led to the definition of psychology as “the science of consciousness”. But it was contended that man’s thought and action are not limited to the stage of “consciousness” alone. Man is active even when he is unconscious. That is why; psychology is called the “science of behavior” which means the study of human nature and activities.

Thus the definition of psychology as the “Science of behavior” has been accepted by the majority. What does the term “behavior” mean?

According to J.B. Watson, “By behavior” we mean an action which can be seen and observed in an objective way.” Behavior is a broad concept. It includes all kinds of activities and experience of an individual. It refers to not only motor or physical activities like walking, talking, writing, but also mental activities like thinking, remembering, imagining and emotional activities, like love, anger and fear. Life manifests through all these activities and behavior is a collective name for all kinds of activities.


Behavior is universal. Every living objects behavior in some way or other. That is why, according to some psychologists “behavior” has been derived from the English term “have”. Behavior is that which all have or possess. But all kinds of behavior are with reference to environment. The same individual may behave differently in different environments and different individuals may behave differently in different environments. Psychology thus studies the behavior of individuals in different contexts.