Human infants' perceptual and cognitive biases reflect their readiness to learn from teaching

mentalistic property attributed to others. Is intentional understanding limited to the immediate perception of attentional behaviours? I will review evidence suggesting that in some primates intentional understanding may extend to coding some epistemic states similar to "knowing" and "not knowing". For example, chimpanzees and orangutans code whether others did or did not see potential targets in the past. It is unclear if monkeys can achieve this level of mentalistic representation. A level of theory of mind that may be beyond the reach of non-humans is the representation of false-beliefs -"wrongly knowing" something. Recent experiments with looking-time measures suggest that human babies may understand false-belief as early as 15 months of age. However, looking measures applied to a rhesus monkey have failed to uncover evidence of false-belief understanding.