Learning is product

Smith [3] proposed that learning is inferential; it is an observable product of mastering knowledge, clarifying meaning, and testing ideas; but cannot be defined. Smith said learning has not occurred regardless of the process unless the individual has observable changes in behavior or capacity. Regarding endurance, changes must last over time. Temporary changes--like slurred speech brought on by drugs or fatigue, and temporary motivation brought on by a rousing speech--do not reflect learning because of cognitive homeostasis. In other words, behavior returns to the normal state when the cause is removed. With forgetting likely to occur with all learning, it remains unclear how long a change must last to be considered learning.