Behavior must be an action and therefore requires what essential element?

Behavior, by definition, involves any observable action taken by an individual. For something to be classified as behavior, it must manifest in a physical form that can be seen or measured. This is why movement is recognized as an essential element of behavior. It implies that there is a physical action that can be observed in the environment.

While awareness, intention, and decision-making can influence behavior and may be important in understanding the context or motivation behind actions, they do not constitute behavior itself. Behavior is grounded in the physical realm—if there is no movement or observable action, there is no behavior to assess. Thus, movement serves as the primary characteristic that defines actions as behaviors.