Abstract: Self-confirmation is not only the key link of Hegel's dialectics， but also the subjectivity principle of modernity. In Economic and Philosophical Manuscripts of 1844， Marx criticizes Hegel's abstract logic that self-confirmation is the sublation of self-alienation， and points out that self is the realization of its own life force and the essential force of the object in the objective activity， thereby confirming its existence. Then Marx creatively combined Feuerbach's perceptual materialism with “the third party” of Hegel， and put forward that “the third being” is the intermediary of mutual confirmation between subjects and objects， which transcends the absolute opposition between subjects and objects， thus breaking through the closed circle of Hegel's self-confirmation and providing the realistic basis for man's self-understanding and self-liberation.

Key words: self-confirmation; dialectics; objectivity; third being