Social learning is learning by example. It is not necessary to be taught something to imitate and adopt the behavior, especially if it is observed to achieve a goal. Most professionals studying domestic abuse believe that seeing violence used successfully in the family or in society at large, especially as a child, encourages its use. Like most social phenomena, it is not possible to demonstrate this by experiment. However, a history of witnessing violence is disproportionately reported in samples of people identified as primary aggressors in relationships.