The main objective of the present dissertation was to investigate the depth of infants’ understanding of beliefs. Specifically, it was crucial to address the “rich” vs. “lean” debate of theory of mind understanding in infancy. The aim of Study 1 was to directly examine whether infants’ looking time pattern commonly observed in the VOE task was replicated when a mechanical toy crane replaced the human agent. Results revealed that infants in the incongruent group did look longer at test than the infants in the congruent group, thus suggesting that infants overattribute false beliefs to inanimate agents.  
	The goal of Study 2 was to examine whether infants’ looking time pattern in the VOE task was replicated using a switch agent paradigm. Specifically, infants watched as a true or false belief was attributed to an agent and then watched as a second, naïve agent search for the object at test. As in Study 1, infants in the incongruent group looked longer at test than the infants in the congruent group, indicating that infants formed expectations for this naïve agent’s actions, once again suggesting that infants overattribute beliefs. 
	Taken together, the findings from the two studies demonstrate that infants broadly overattribute beliefs to any agents, even those to whom adults would not attribute beliefs. These findings challenge the “rich” view of theory of mind understanding in infancy given that this view posits that infants have a sophisticated understanding of mental states.