These are also strong incentives for effective learning. Praise stimulates average and inferior children but has less effect on those of superior intelligence. Reproof is felt most by superior children, but girls seem more susceptible to praise them do boys. Regardless of age, sex or initial ability, praise is the most effective of the incentives. Reproof seems to be less effective than blame with young children, but Harlock (1920) generalized still accepted by contemporary investigation, that praise is more effective stimulus in motivating both immediate and long-contained tasks.