We review recent anticipatory looking and violation-of-expectancy studies suggesting that infants and young preschoolers have spontaneous (implicit) understanding of mind despite their known problems until later in life on elicited (explicit) tests of false-belief reasoning. Straightforwardly differentiating spontaneous and elicited expressions of complex mental state understanding in relation to an implicit-explicit knowledge framework may be challenging; early action predictions may be based on behavior rules that are complementary to the mentalistic attributions under consideration. We discuss that the way forward for diagnosing early mentalism is to analyze whether young candidate mind-readers’ visual orienting cohere across different belief-formation by belief-use combinations. Adopting this formal cognitive analysis, we conclude that whilst some studies come tantalizingly close to sign-posting mentalism in infants and young children’s spontaneous responses, the bulk of evidence for early mentalism grades into behaviorism.