The article discusses two contrasting views on how children understand the mind: the "theory theory" and the "simulation theory." The theory theory posits that children's understanding of the mind is akin to scientific theories, involving abstract, unobservable entities and laws that explain mental states and behaviors. This view suggests that children's understanding of the mind develops through theory change, similar to scientific theories. The simulation theory, on the other hand, argues that children understand the mind by simulating their own mental states to predict and explain others' behaviors, using their own mind as a model. The article argues that the theory theory is better supported by developmental evidence. It outlines how children's understanding of the mind evolves from a non-representational desire-perception theory at 2 years old, to a more intermediate phase at 3 years old where belief is understood as a non-representational construct, and finally to a representational belief-desire theory by 5 years old. This development is characterized by the accumulation of counter-evidence, the development of auxiliary hypotheses, and the eventual reorganization of knowledge into a more comprehensive theory. The simulation theory is critiqued for failing to account for the complexity and predictive power of children's mental theories, as well as for not explaining the development of representational understanding. The article also highlights that children's understanding of mental states is not merely descriptive but involves interpretation and prediction, which aligns more closely with the theory theory. The simulation theory's emphasis on the child's own mental states as the basis for understanding others is contrasted with the theory theory's focus on abstract, representational constructs. The article concludes that the theory theory provides a more comprehensive explanation of children's mental development, including their ability to make predictions, interpret evidence, and develop a coherent understanding of mental states.The article discusses two contrasting views on how children understand the mind: the "theory theory" and the "simulation theory." The theory theory posits that children's understanding of the mind is akin to scientific theories, involving abstract, unobservable entities and laws that explain mental states and behaviors. This view suggests that children's understanding of the mind develops through theory change, similar to scientific theories. The simulation theory, on the other hand, argues that children understand the mind by simulating their own mental states to predict and explain others' behaviors, using their own mind as a model. The article argues that the theory theory is better supported by developmental evidence. It outlines how children's understanding of the mind evolves from a non-representational desire-perception theory at 2 years old, to a more intermediate phase at 3 years old where belief is understood as a non-representational construct, and finally to a representational belief-desire theory by 5 years old. This development is characterized by the accumulation of counter-evidence, the development of auxiliary hypotheses, and the eventual reorganization of knowledge into a more comprehensive theory. The simulation theory is critiqued for failing to account for the complexity and predictive power of children's mental theories, as well as for not explaining the development of representational understanding. The article also highlights that children's understanding of mental states is not merely descriptive but involves interpretation and prediction, which aligns more closely with the theory theory. The simulation theory's emphasis on the child's own mental states as the basis for understanding others is contrasted with the theory theory's focus on abstract, representational constructs. The article concludes that the theory theory provides a more comprehensive explanation of children's mental development, including their ability to make predictions, interpret evidence, and develop a coherent understanding of mental states.