structural:scholar_edition, structural:reformatting
Science of Logic

Hegel's concept of logic differs greatly from that of the ordinary English sense of the term. This can be seen, for instance, in such metaphysical definitions of logic as "the science of things grasped in thoughts that used to be taken to express the essentialities of the things." As Michael Wolff explains, Hegel's logic is a continuation of Kant's distinctive logical program. Its occasional engagement with the familiar Aristotelian conception of logic is only incidental to Hegel's project. Twentieth-century developments by such logicians as Frege and Russell likewise remain logics of formal validity and so are likewise irrelevant to Hegel's project, which aspires to provide a metaphysical logic of truth.

There are two texts of Hegel's Logic. The first, The Science of Logic (1812, 1813, 1816; bk.I revised 1831), is sometimes also called the "Greater Logic." The second is the first volume of Hegel's Encyclopedia and is sometimes known as the "Lesser Logic." The Encyclopedia Logic is an abbreviated or condensed presentation of the same dialectic. Hegel composed it for use with students in the lecture hall, not as a substitute for its proper, book-length exposition.

Hegel presents logic as a presuppositionless science that investigates the most fundamental thought-determinations, or categories, and so constitutes the basis of philosophy. In putting something into question, one already presupposes logic; in this regard, it is the only field of inquiry that must constantly reflect upon its own mode of functioning. The Science of Logic is Hegel's attempt to meet this foundational demand. As he puts it, " logic coincides with metaphysics." In the words of scholar Glenn Alexander Magee, the logic provides "an account of pure categories or ideas which are timelessly true" and which make up "the formal structure of reality itself".

It is important to see, however, that Hegel's metaphysical program is not a return to the Leibnizian - Wolffian rationalism critiqued by Kant, which is a criticism Hegel accepts. In particular, Hegel rejects any form of metaphysics as speculation about the transcendent. His procedure, an appropriation of Aristotle's concept of form, is fully immanent. More generally, Hegel agrees wholeheartedly with Kant's rejection of all forms of dogmatism and also agrees that any future metaphysics must pass the test of criticism. It is the assessment of scholar Stephen Houlgate that Hegel's method of immanent logical development and critique is historically unique.

Philosopher Béatrice Longuenesse holds that this project may be understood, on analogy to Kant, as "inseparably a metaphysical and a transcendental deduction of the categories of metaphysics." This approach insists, and claims to demonstrate, that the insights of logic cannot be judged by standards external to thought itself, that is, that "thought... is not the mirror of nature." Yet, she argues, this does not imply that these standards are arbitrary or subjective. Hegel's translator and scholar of German idealism George di Giovanni likewise interprets the Logic as (drawing upon, yet also in opposition to, Kant) immanently transcendental; its categories, according to Hegel, are built into life itself, and define what it is to be "an object in general."

Books one and two of the Logic are the doctrines of "Being" and "Essence." Together they comprise the Objective Logic, which is largely occupied with overcoming the assumptions of traditional metaphysics. Book three is the final part of the Logic. It discusses the doctrine of "the Concept," which is concerned with reintegrating those categories of objectivity into a thoroughly idealistic account of reality. Simplifying greatly, Being describes its concepts just as they appear, Essence attempts to explain them with reference to other forces, and the Concept explains and unites them both in terms of an internal teleology. The categories of Being "pass over" from one to the next as denoting thought-determinations only extrinsically connected to one another. The categories of Essence reciprocally "shine" into one another. Finally, in the Concept, thought has shown itself to be fully self-referential, and so its categories organically "develop" from one to the next.

It is clear then, that in Hegel's technical sense of the term, the concept (Begriff, sometimes also rendered "notion," capitalized by some translators but not others) is not a psychological concept. When deployed with the definitive article ("the") and sometimes modified by the term "logical," Hegel is referring to the intelligible structure of reality as articulated in the Subjective Logic. (When used in the plural, however, Hegel's sense is much closer to the ordinary dictionary sense of the term.)

Hegel's inquiry into thought is concerned to systematize thought's own internal self-differentiation, that is, how pure concepts (logical categories) differ from one another in their various relations of implication and interdependence. For instance, in the opening dialectic of the Logic, Hegel claims to display that the thought of " being, pure being – without further determination" is indistinguishable from the concept of nothing, and that, in this "passing back and forth" of being and nothing, " each immediately vanishes in its opposite. " This movement is neither one concept nor the other, but the category of becoming. There is not a difference here to which one can "refer," only a dialectic that one can observe and describe.

The final category of the Logic is "the idea." As with "the concept", the sense of this term for Hegel is not psychological. Rather, following Kant in The Critique of Pure Reason, Hegel's usage harks back to the Greek eidos, Plato 's concept of form that is fully existent and universal: "Hegel's Idee (like Plato's idea) is the product of an attempt to fuse ontology, epistemology, evaluation, etc., into a single set of concepts."

The Logic accommodates within itself the necessity of the realm of natural-spiritual contingency, that which cannot be determined in advance: "To go further, it must abandon thinking altogether and let itself go, opening itself to that which is other than thought in pure receptivity." Simply put, logic realizes itself only in the domain of nature and spirit, in which it attains its "verification." Hence the conclusion of the Science of Logic with "the idea freely discharging itself" into "objectivity and external life" – and, so too, the systematic transition to the Realphilosophie.