Quantifying intentions: Developmental change in conceiving intentions

An experiment was designed to test children's insight that behaviour may increase (positive relation) or decrease (negative relation) as a function of intention intensity. Behaviour variation was depicted in terms of time (duration) and distance, and Ss inferred behaviour variations from variation in intention intensity, and vice versa. Response variation related only to age, and showed that understanding of positive relations was developed by five years of age, whereas understanding of negative relations was developed between the ages of seven and nine years.