How are knowledge and action compatible as modes of activity of a unified rational subject? In the section of his Encyclopedia called ”Psychology”, Hegel takes up this problem of the two-sidedness of human subjectivity. For Hegel, the division between these two sides of spirit is a necessary one, but they only present two sides of one coin. Intelligence and the will cannot be fixed and independent capacities of a rational subject. Rather, they are steps in the developing trajectory of spirit, the purpose of which is ”to liberate itself to its own self.” (§442R).

Whereas the ”Anthropology” discusses embodiment and the ”Phenomenology” studies the consciousness, only after them at the stage of Psychology do we fully get spirit’s ”universal modes of activity” (§440R) into view. The Psychology establishes a developmental account of how spirit raises above natural determinacy as it recognizes the world as rational and becomes able to realize its ends in it.

The theoretical part of the Psychology includes the moments of intuition, representation, and thinking. Being first determined in intuition, our representational capacities allow us to posit the object of knowledge as not something foreign, but as something shaped by our cognitive activity. In being able to form representations as linguistic signs, we distance ourselves from the immediacy of the object relation, and become first capable of thought. The practical part starts with the subject and the aims that it wants to realize in the world. Whereas theoretical spirit is observational and leaves the object untouched, practical spirit is characterized by Hegel as negative: it aims at bringing itself into existence. Through the steps of practical feeling, drives and wilfulness, and happiness, Hegel shows how subjective action comes about. 

Both the theoretical and practical spirit complement each other in that they realize themselves as opposites — theoretical spirit going from the object to the subject, practical spirit from the subject to the object. Hegel thereby shows that neither of these forms can be fixed, but each presuppose the other. Theoretical spirit does not merely passively take up knowledge of the world but is active and in that it raises the given object into the form of reason and thereby objectifies itself. Similarly practical spirit also has a passive side to it, as it presupposes its content as given to it by theoretical thought.

But, even as interdependent, both forms of spirit turn out to be unsatisfactory in the end, for they presuppose an isolated subject whose freedom is conceived of merely as abstract. Only in the unity of the theoretical and the practical do we get the category of ”free spirit”, a point of transition to objective spirit. My main interpretative task is to explain why Hegel takes it that spirit must necessarily overcome the division of theory and practice. Based on the work of Christoph Menke, I show that this is because spirit’s recognition of the world as rational is not merely passive observation, but an activity of transformation.