In popular use, "positive reinforcement" is often used as a synonym for "reward", with people (not behavior) thus being "reinforced", but this is contrary to the term's consistent technical usage, as it is a dimension of behavior, and not the person, which is strengthened. "Negative reinforcement" is often used by laypeople and even social scientists outside psychology as a synonym for "punishment". This is contrary to modern technical use, but it was B.F. Skinner who first used it this way in his 1938 book. By 1953, however, he followed others in thus employing the word "punishment", and he re-cast "negative reinforcement" for the removal of aversive stimuli.