Immediately after introducing recognition, Kant brings apperception and the unity of apperception into the discussion. The acts by which we achieve recognition under concepts are acts of apperception. By ‘apperception’, Kant means the faculty or capacity for judging in accord with a rule, for applying concepts. Apperceiving is an activity necessary for and parallel to perceiving (A120). This is one of the senses in which Leibniz used the term, too. To achieve recognition of a unified object, the