“…He also maintained that these motivative variables were antecedent events and separate from all types of stimulus variables. Several years later, Keller and Schoenfeld (1950) elaborated on Skinner's position in the section titled, ''A drive is not a stimulus'' (p. 276), where they stated, ''a drive has neither the status, nor the functions, nor the place in a reflex that a stimulus has … it is not, in itself either eliciting, reinforcing, or discriminative'' (p. 276). Keller and Schoenfeld also suggest that the term ''establishing operation'' be used to distinguish the effects of deprivation, satiation, and aversive stimulation from various stimulus effects.…”