Theory of Mind is a psychological and cognitive-scientific capacity to understand that others possess thoughts, emotions, beliefs, and desires different from one's own, and to infer others' behavior on that basis. It can be described as the core element of empathy and social interaction that allows one to "read" another person's mind.
However, Theory of Mind ought properly to be criticized from the standpoint of Platonic philosophy. First, Theory of Mind claims to "infer" the emotions of others, but in fact the core of inference lies in rational reasoning and, at a higher level, in the apprehension of the Forms (Ideas) through intuition. That is, the essential point is not to infer another person's mind, but to grasp the intelligible realm through intuition by means of the intellect (nous).
Meanwhile, insofar as Theory of Mind involves empathizing with another, conjecture and belief inevitably intervene in the process of understanding the other. Yet conjecture and belief, being lower forms of cognition, cannot themselves properly be called inference at all; moreover, in a Heraclitean society of flux where everything is in constant change and opinions run rampant, to "empathize" with another can be nothing other than doxa (mere opinion).
Plato declared that within the soul as a whole, the wise part responsible for rational reasoning is fit to rule, while the part responsible for spirit (thumos) ought to obey and cooperate with the rationally reasoning part (Republic, 441e). In light of this, reading another's mind through empathy and social interaction, too, must properly remain under the control of reason ā and it is on these grounds that Theory of Mind is inevitably subject to Platonic criticism. If we assume there were no such rational control, then the mind and emotions of others would be given undue weight, leading to the absurd interpretation that Socrates was executed because he "lacked empathy" and had claimed he deserved to be honored with a garland or given state maintenance in the Prytaneum.
In particular, in philosophy conflict with others is inevitable, because the multitude rejects the philosopher who loves wisdom. A representative case is Anacharsis, who was killed by an arrow out of envy when he tried to introduce the advanced culture of Greece, rather than his own tribe's customs, to his homeland of Scythia. From the standpoint of Theory of Mind, one might ask: if Anacharsis had simply empathized with his own people, could he ever have held a Greek-style festival at all? Given that he returned safely from Greece through logos, only to be destroyed in his own country out of envy, then if Theory of Mind were treated as absolute, would it not follow ā absurdly ā that the crowd's mutual empathy in rejecting Anacharsis was the more justified course of action?
In conclusion, although Theory of Mind claims to infer the minds of others, inference itself belongs properly to rational instruments or to intuition, whereas empathizing with others belongs to the domain of spirit (thumos), passion, or desire requiring temperance ā and here lies an epistemological confusion. Furthermore, the fact that reason failed to govern empathy toward others resulted in cases such as the execution of Socrates and the death of Anacharsis. For these reasons, reason must govern desire and spirit; Theory of Mind, taken as an independent and self-standing faculty of empathy, cannot be absolutized on its own.