 As in early  Mohist thought,  the focus of later Mohist epistemology is not on the justification or truth of beliefs, or propositional attitudes, but on knowing how to distinguish which things or situations are shì 是 (this) for some term and which are fēi 非 (not-this). As in the earlier texts, the core expression of knowledge is knowing how to apply terms to things correctly. However, the Dialectics identifies new aspects of knowledge to explain cases such as when someone is able to make a correct assertion about something but not to identify it perceptually or when someone can recognize a thing under one name but not another. 