The addition of an unpleasant stimulus following a behavior to decrease the likelihood that the behavior will occur again. This involves presenting something aversive as a consequence of undesired behavior.
Systematized by B.F. Skinner in the 1950s, using 'positive' from Latin 'positivus' (adding) and 'punishment' from Old French 'punissement.' Skinner's terminology emphasizes the mathematical operation (addition) rather than the emotional valence, though this often creates confusion.
Positive punishment is what most people simply call 'punishment' - adding something bad like a speeding ticket or extra chores. The 'positive' just means you're adding a consequence, not that the punishment is good! This mathematical naming system trips up even psychology students.
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