The article is concerned with the epistemological background of Hannah Arendt’s philosophy. It focuses on the notion of common sense that plays a central role in Arendt’s work. The origin of Arendt’s notion of common sense lies in her interpretation of Kant, and the author tries to state the inadequacies of Arendt’s interpretation of Kant with respect to the notion of common sense. The focus is not on the application to political philosophy but rather on Kant’s theory of judgement, and it is shown that whereas Kant’s aim was a unified theory of rationality, Arendt, mostly unintentionally, narrows the scope of the theory to conscious consideration of others in decision making. Textual evidence aside, the thesis of the article is supported by a reductive argument that distinguishes the purported theory of the meaning of judgements from Arendt’s approach, in order to show the latter’s conformist implication.