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Jacobi, Friedrich Heinrich (1743–1819)


Friedrich Heinrich Jacobi was a leading representative, with Johann Georg Hamann, of the philosophy of feeling and a major critic of Immanuel Kant. He was born in Düsseldorf on the Rhine. Jacobi received an education preparing him for a business career, but an inner urge drove him to the pursuit of philosophical studies. He studied the works of Claude-Adrien Helvétius, Jean-Jacques Rousseau, Ferguson, and Benedict de Spinoza, the last of which had a negative influence on him, provoking opposition and criticism; he was also influenced by the English philosophers of feelingthe earl of Shaftesbury and others. His friend Hamann, a kindred spirit, lived in his home for a long period, and his influence on Jacobi cannot be overestimated. In 1804, Jacobi was appointed president of the Academy of Sciences in Munich. He was in literary contact with the prominent thinkers of his timeMoses Mendelssohn, Karl Leonhard Reinhold, Jakob Friedrich Fries, and Johann Wolfgang von Goethe. His discussions with his contemporaries are as important for the understanding of his philosophy as are his original works.

Jacobi developed a philosophy of feeling and faith. He was critical of speculations leading to the concept of the prevalence of necessary laws above freedom, hence Jacobi's rejection of Spinoza's pantheism and of the philosophy of Johann Gottlieb Fichte, Friedrich von Schelling, and G. W. F. Hegel, in which there are manifest pantheistic tendencies. Because of Jacobi's concept of the primacy of freedom, he found that the actions of man are not to be deduced from his thinking, for thinking is not the primary force in man. The history of man is not the result of his mode of thought; rather, the former determines the latter. Herein is anticipated the method of the historical school of law as it was later developed by Friedrich Karl von Savigny. For Jacobi the immediately given is the determining factor in our cognition of cultural phenomena. Objects have to be given to us through immediate feeling or faith before thought comes into play. The task of discursive thinking is to observe, analyze, compare, and order perceptions by reducing them to their fundamental principles. But unless something real is previously given through feeling, discursive thinking cannot take place.

Jacobi was a master of criticism. His strength lay in grasping a system of thought as a whole and detecting those elements in it that are incompatible. This capacity of critical analysis is manifest in his appraisal of dogmatic rationalism and the critical philosophy. Jacobi subjected both Spinoza and Kant to severe criticism. He pointed to hidden contradictions and inconsistencies in both their systems. The dogmatic rationalism of Spinoza employs the mathematical method in the realm of metaphysics; it accepts as real only what can be proven and deduced mathematically. By this method, however, neither God nor freedom can be maintained. These ideas cannot be deduced by an absolute system of causality, which is the essence of Spinozism. Absolute necessity leads to atheism, and the denial of freedom leads to fatalism. To Jacobi, Spinozism and pantheism were synonymous terms, and pantheism was identical with dogmatic rational atheism. (He ignored the possibility of interpreting Spinoza's system as acosmism instead of as atheisman interpretation that was first suggested by Salomon Maimon and then by Hegel.)

Jacobi's ethicoreligious worldview is the background of this criticism of Spinoza. While recognizing the dangers implied in Spinozism, Jacobi and Gotthold Ephraim Lessing were the first to acknowledge the philosophical genius of Spinoza. Through Jacobi's discussions with Mendelssohn about Spinozism and Lessing's relation to it, in the course of which the arguments for and against Spinoza were brought forth, Spinoza's philosophy became a force in the intellectual life of the time; it acquired a universal significance. Spinoza and Kant were two opposing poles of thought for Jacobi. For the former all being, including man, is determined by necessary laws; for the latter freedom and creativity are the essence of man. The whole period of the development of post-Kantian speculative idealism was determined by the two intellectual forces: the dogmatic rationalism of Spinoza and the critical philosophy of Kant. Jacobi was critical of the philosophy of speculative idealism (Fichte, Schelling, and Hegel) for its manifestation of Spinozistic tendencies.

Jacobi on Kant

Jacobi's enthusiasm for Kant's precritical essay Der einzig möglicher Beweisgrund zu einer Demonstration des Daseins Gottes (The only possible ground for a demonstration of God's existence) is indicative of his conception of the method by which we can attain knowledge of reality. Kant had shown in this work that the absolute and unconditioned being must be grasped as existing in and through itself, not as a predicate or as a consequence of something else. The attainment of some reality that is simple, insoluble, and immediately given is the ultimate aim in our striving for certainty. Cognition by way of discursive thought cannot attain certainty. A method of deduction of consequences from premises is an endless process that can never attain the original unconditional and primary being. Certainty is acquired only in an immediate perception of a reality not requiring any deduction.

Jacobi admired Spinoza because he had reversed the whole process of philosophizing as it was known since Aristotle. Instead of proceeding from the phenomena of experience, leading gradually to being as such, Spinoza started with a definition of substance as something that is conceived in itself and through itselfthat is, a simple and immediately given reality. This simple and indissoluble datum is, however, according to Jacobi, not free from contradiction. Spinoza's substance is not a free, independent, self-sufficient being, but a necessary and causally bound being. The God of Spinoza is nothing else but a manifestation of the logical-mathematical determination of being.

The critical philosophy can be maintained only if it consistently removes all traces of a dogmatic, realistic nature. The concept of a thing-in-itself has to be completely eliminated because it is incompatible with the system as a whole. The Kantian position is, according to Jacobi, pure idealism. As such it cannot retain the concept of things in themselves. The Critique of Pure Reason deduces the objects from the constitution of our cognitive capacity. It has therefore to deny objective reality existing independently of and beyond the conditions of cognition. The object has to be completely resolved in subjective presentations of our mind. Kantian philosophy is thus interpreted by Jacobi as pure subjective idealism. Since we perceive the objects through forms of sensibility (space and time) and concepts of understanding, constituting the human capacity of cognition, the "external" objects cannot be beyond us. According to Jacobi, René Descartes intended by the principle cogito ergo sum to deduce the totality of the inner subjective world from the consciousness of the self as a thinking subject. Self-consciousness of oneself as a thinking being is the primary condition of man's knowledge of the inner world. In a similar manner Kant tried to prove that external objects are likewise conditioned by and dependent on the subject with its forms of sensibility and understanding. Hence, the subjective idealism of Descartes was extended by Kant to encompass the world of objects, too. The Kantian position is thus, according to Jacobi, universal idealism, but since he took Kant to mean that the cognition of things is determined by the individual ego and not by the objective mind as it is presented in scientific thought, universal idealism, according to Jacobi, is a system of absolute subjectivity, which implies a "nihilism" with reference to the objects. This system recognizes only the ego as real; it is thus speculative egoism. Jacobi found this position self-contradictory. Sensibility is a receptive function, according to Kant. But a consistent idealism excludes a receptive capacity in the process of cognition. It is incongruous with idealism to assume the reality of things-in-themselves existing independently of our mind, yet these things are supposed by Kant to supply the material of experience that affects our senses. The first part of the Kantian Critique deals with the forms of sensibility as a receptive capacity. Thus, things-in-themselves are assumed, by which our sensibility is affected. "Hence we cannot enter into the Critique without assuming things-in-themselves, but we cannot retain this assumption upon leaving the Critique."

Since Jacobi understood the Kantian position as subjective idealism, he did not consider the second edition of the Critique of Pure Reason an improvement on the first. The Kantian philosophy that Jacobi took to be a form of pure subjective idealism is presented in the first edition of the Critique, and this he took to be its genuine and adequate presentation. To Jacobi belongs the priority of recognizing the difference between the two editions, but he was wrong in its evaluation. He failed to grasp the essential characteristic of critical idealism, which is grounded in analysis of objective scientific cognition and not in analysis of the process of cognition of the individual subject. The problem posed by Kant was How are synthetic propositions a priori in mathematics and natural science possible?, not How is cognition of the individual subject as a psychological phenomenon possible? Whereas the Kantian inquiry constitutes the essence of the transcendental method, leading to objective idealism, the investigation of the individual process of cognition appertains to the psychological method, resulting in subjective idealism. The second edition of the Critique, which tries to eliminate the psychological sections of the first edition, is the preeminent presentation of the transcendental method.

Faiththe Sense of Reality

In opposition to the critical philosophy, which is, according to Jacobi, absolute subjectivity, he proposed a thesis of absolute objectivity. The objective reality of things-in-themselves existing beyond man and independently of the human cognition is based for Jacobi on an original, immediate certainty that does not require any proof or demonstration. The certainty of the existence of things in themselves is based on faith.

Our consciousness presupposes the reality of things as a necessary correlate of cognition. The idealistic position contradicts an assumption that is inherent in every act of cognition of an object of experience. To be sure, the reality of the things cognized cannot be conclusively derived from the process of cognition as such, which is a subjective phenomenon, but only from the immediate sense of reality accompanying every act of cognition of an object. This sense of reality, which cannot be accounted for logically but is nonetheless present in our mind, is designated by Jacobi by such terms as faith, feeling, and, later, revelation.

With Kant Jacobi recognized that analysis of cognition cannot lead to things-in-themselves, since the validity of the categories is confined to the realm of experience and does not extend beyond it. But the Kantian Critique had also shown that reason leads to a realm of faith in addition to mere cognition. Hence, an object that cannot be proven as real on the basis of cognition may still be real on the basis of faith. Kant employed the concept of faith only with reference to the moral and religious realm, but Jacobi extended the scope of faith to include the knowledge of things-in-themselves. In recognizing the validity of faith for the theoretical realm, Jacobi followed David Hume, who designated the feeling of reality of the natural human consciousness as faith. The skepticism of Hume showed that the reality of things cannot be derived from sense perception. Analysis of perception cannot lead to cognition of substance and causality; only through faith can we know the reality of things. Hume thus ascribed to faith a positive theoretical function inasmuch as it is a source of knowledge of the reality of the things of experience. The belief in the reality of things, which accompanies our sensuous experience throughout our lives, is incomprehensible, but, according to Jacobi, it commands certainty just as if it were an act of revelation. He understood by revelation a certainty that we are aware of but which we cannot explain rationally. This conception of the belief in the reality of things is radically different from naive realism and commonsense philosophy. The latter does not realize the extraordinary nature and the problematic character of the concept of reality, of things-in-themselves. Naive realism takes for granted that we perceive things as they are. Jacobi, however, realized the miraculous nature of such a belief. The possibility of transition from consciousness to things, from the subject to objects, cannot be comprehended by our understanding. Jacobi was right to affirm the position of critical idealism that we can know of things only what we ourselves put into them. While we cannot cognize things-in-themselves, our belief in their reality can be accounted for as something irrational that is an indispensable ingredient of human consciousness. Our rational thinking cannot lead us to cognition of reality of things-in-themselves. However, the necessary condition of the existence of man as a conscious being is grounded in an incomprehensible and irrational act of faith commanding certainty that is not subject to any doubt. In face of this belief as a necessary condition of human consciousness, the arguments of rationalism, of critical philosophy, and of skepticism are powerless.


Jacobi's philosophy of religion is grounded in the same principle on which his theory of cognition of reality is founded. The concept of faith as having a theoretical function is the ground of the certainty of real objects beyond us and of a supersensuous reality. This immediate certainty of reality is present in our consciousness of God as it is present in our perception of objects. Through belief man has the capacity of intuiting God. Dogmatic religionists maintain that through an act of faith God reveals himself to man by grace. For Jacobi faith is a mode of cognition or a form of intellectual intuition. And this is not an exclusively religious phenomenon, for through belief man likewise perceives the reality of things of experience. The distinction between the reality of the things and the transcendent, supersensuous reality is that the former reveals itself through an external perception, whereas the latter is intuited through an internal revelation. Both forms of revelation constitute the very essence of human existence as a conscious being.

For Kant, it is impossible through faith to transcend the sphere of the subject, but for Jacobi we are aware through faith of a reality that is not subjective, since in the act of faith the nature of the real thing reveals itself to us. Faith thus commands not only ethical certainty, as Kant held, but also theoretical certainty. To be sure, the transcendent reality cannot be known by the forms of understanding that are confined to the realm of experience. But faith as a function of reason (Vernunft ) is capable of transcending experience and thus can perceive the supersensuous by an act of intellectual intuition.

Intellectual intuition, which is attained through faith, overcomes the Kantian dualism of sensibility and understanding, which is a necessary condition of cognition of objects of experience. Kant considered intellectual intuition an idea of knowledge of the infinite mind (intellectus archetypus ), which is not attainable by the finite, human mind. But for Jacobi intellectual intuition is attained through faith, or immediate feeling. Jacobi thus prepared the way for the post-Kantian speculative metaphysicians to consider intellectual intuition a capacity of human reason.


By ascribing to belief the function of knowledge of things-in-themselves and of the existence of God and of freedom, Jacobi disregarded the essential difference between the theoretical and the ethical realms. Kant's concept of faith is a new principle of validity but not a mode of knowledge. In the Critique of Practical Reason Kant discovered an "unconditioned" in opposition to the conditioned reality of experience. God and freedom as ideas of practical reason are not metaphysical things but principles of ethical conduct. It is the unconditioned of freedom and the "ought to be," not the existence of transcendent reality, that is discovered through faith.

Jacobi is rightly critical of the dogmatic rationalism of the Enlightenment; he realized the limitations of rational thought in face of the endlessness of that which is problematic. But he was wrong in subordinating the realm of science, which is grounded in discursive thinking, to that of feeling and faith. He did not realize the problem involved in his concept of belief and immediate feeling as the highest means of attaining knowledge of reality. The appeal to feeling, belief, and immediate evidence opens up possibilities for abuse and willful arbitrariness. Feeling and immediate sense of reality are subjective, and whenever a capacity of the subject is elevated to a principle of knowledge, objective truth is in jeopardy. The rightful place of faith is therefore the ethical and the religious realm, which is concerned with the "ought," not with being as it is. Theoretical knowledge of reality can be attained only by discursive thinking, which is the scientific method.

Jacobi said of himself that he was a pagan in his mind but a Christian in his heart. He thus recognized the conflict between reason and faith that he caused by the extended role he ascribed to faith. His belief in the reality of things-in-themselves, of a supersensuous being, and of freedom not only claims ethical and religious validity but also pretends to possess the rank of theoretical knowledge; it is therefore in conscious disagreement with reason. The price we pay for extending the scope of faith is its clash with reason.

See also Pantheismusstreit.


works by jacobi

Über die Lehre des Spinozas, in Briefen an Herrn Moses Mendelssohn. Breslau: G. Löwe, 1785.

David Hume über den Glauben, oder Idealismus und Realismus. Breslau: G. Löwe, 1787.

Sendschreiben an Fichte. Hamburg, 1799.

Über das Unternehmen des Kritizismus, die Vernunft zu Verstande zu bringen und der Philosophic überhaupt eine neue Absicht zu geben. Hamburg, 1802.

Von den göttlichen Dingen und ihrer Offenbarung. Leipzig, 1811.

Jacobi's Werke, 6 vols. Edited by F. Roth. Leipzig: G. Fleischer, 18121825.

Hauptschriften zum Pantheismusstreit zwischen Mendelssohn und Jacobi. Edited by M. Scholz. Berlin: Reuther and Reichard, 1916.

works on jacobi

Ahlers, Rolf. "Vitalism and System: Jacobi and Fichte on Philosophy and Life." Idealistic Studies 33 (1) (2003): 83113.

Behler, Ernst, ed. Philosophy of German Idealism: Fichte, Jacobi, and Schelling. New York: Continuum, 1987.

Bowie, Andrew. "Rethinking the History of the Subject: Jacobi, Schelling, and Heidegger." In Deconstructive Subjectivities, edited by Simon Critchley. Albany: State University of New York Press, 1996.

Di Giovanni, George. "The Early Fichte as Disciple of Jacobi." Fichte Studien 9 (1997): 257273.

Di Giovanni, George. "Fichte's Rhetoric of Deception: Reflections on the Early Fichte in the Spirit of Jacobi." Revue Internationale de Philosophie 49 (191) (1995): 978.

Di Giovanni, George. "From Jacobi's Philosophical Novel to Fichte's Idealism: Some Comments on the 179899 'Atheism Dispute.'" Journal of the History of Philosophy 27 (1989): 75100.

Di Giovanni, George. "The Jacobi-Fichte-Reinhold Dialogue and Analytical Philosophy." Fichte Studien 14 (1998): 6386.

Franks, Paul. "All or Nothing: Systematicity and Nihilism in Jacobi, Reinhold, and Maimon." In The Cambridge Companion to German Idealism, edited by Karl Ameriks. New York: Cambridge University Press, 2000.

Janssens, David. "The Problem of the Enlightenment: Strauss, Jacobi, and the Pantheism Controversy." Review of Metaphysics 56 (3) (2003): 605631.

Lévy-Bruhl, L. La philosophie de F. H. Jacobi. Paris: Alcan, 1894.

Milbank, John. "Knowledge: The Theological Critique of Philosophy in Hamann and Jacobi." In Radical Orthodoxy: A New Theology, edited by John Milbank, Catherine Pickstock, and Graham Ward. New York: Routledge, 1999.

Schmidt, F. U. F. H. Jacobi. Heidelberg, 1908.

Schmidt, James. "Liberalism and Enlightenment in Eighteenth-Century Germany." Critical Review 13 (12) (1999): 3153.

Snow, Dale E. "F. H. Jacobi and the Development of German Idealism." Journal of the History of Philosophy 25 (1987): 397415.

Solomon, Robert C. Introducing the German Idealists: Mock Interviews with Kant, Hegel, Fichte, Schelling, Reinhold, Jacobi, Schlegel, and a Letter from Schopenhauer. Indianapolis: Hackett, 1981.

Westphal, Kenneth R. "Hegel's Attitude toward Jacobi in the 'Third Attitude of Thought toward Objectivity.'" Southern Journal of Philosophy 27 (1989): 135156.

Williams, Robert R. "The Other: F. H. Jacobi and German Idealism." In Hegel on the Modern World, edited by Ardis Collins. Albany: State University of New York Press, 1995.

Wurzer, Wilhelm S. "Between Idealism and Dasein : Friedrich Heinrich Jacobi." Dialogos 11 (1977): 123136.

Zirngiebl, E. F. H. Jacobi. Vienna, 1867.

Samuel Atlas (1967)

Bibliography updated by Tamra Frei (2005)

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