Human adults have a strong bias to invoke intentional agents in their intuitive explanations of ordered wholes or regular compositions in the world. Less is known about the ontogenetic origin of this bias. In 4 experiments, we found that 9-to 10-month-old infants expected a human hand, but not a mechanical tool with similar affordances, to be the primary cause of nonrandom sampling events that resulted in regular color patterns in visual displays. Infants did not have such expectations when the sampling appeared random with no regular compositions in the outcome. These findings provide the first evidence that by about 9 months of age, infants infer the presence of an intentional agent from the perception of regularity.