The five lectures that constitute Reason and Existenz were delivered at the University of Groningen, Holland, in the spring of 1935. In these lectures, the author knits together the various themes that are elaborated in his many philosophical writings. Reason and Existenz is thus both a helpful summary of and an excellent introduction to the author’s philosophy.

Ezistenz and Philosophy

Jaspers defines philosophy as the elucidation of Existenz (Existenzerhellung). (The term “Existenz” is retained because the English “existence” is not its equivalent.) This elucidation of Existenz needs to be sharply contrasted with any attempt at a conceptualization of Existenz through objectively valid and logically compelling categories. Jaspers denies that a unifying perspective of the content of existential reality is possible. Nevertheless, a clarification of or elucidation of Existenz as it expresses itself in concrete situations can be productively undertaken. According to Jaspers, the philosopher is the one who strives for such clarification.

Jaspers finds in the concrete philosophizing of Søren Kierkegaard and Friedrich Nietzsche a profound exemplification of the philosophical attitude. Both, in their interest to understand existential reality from within, had serious reservations about any program that intended to bring thought into a single and complete system, derived from self-evident principles. Any claim for a completed existential system affords nothing more than an instance of philosophical pretension. Existenz has no final content; it is always “on the way,” subject to the contingencies of a constant becoming. Kierkegaard and Nietzsche, in grasping this fundamental insight, uncovered the existential irrelevancy of Georg Wilhelm Friedrich Hegel’s system of logic. It was particularly Kierkegaard, in his attack on speculative thought, who brought to light the comic neglect of Existenz in the essentialism and rationalism of Hegel. Kierkegaard and Nietzsche further laid the foundations for a redefinition of philosophy as an elucidation of Existenz through their emphasis on the attitudinal, as contrasted with the doctrinal, character of philosophy. They set forth a new intellectual attitude toward life’s problems. They developed no fixed doctrines that can be abstracted from their thinking as independent and permanent formulations. They were both suspicious of scientists who sought to reduce all knowledge to simple and quantifiable data. They were passionately interested in the achievements of self-knowledge. Both taught that self-reflection is the way to truth. Reality is disclosed through a penetration to the depths of the self. Both realized the need for indirect communication and saw clearly the resultant falsifications in objectivized modes of discourse. Both were exceptions—in no sense models for followers. They defy classification under any particular type and shatter all efforts at imitation. What they did was possible only once. Thus the problem for us is to philosophize without being exceptions, but with our eyes on the exception.

Encompassing and Being

At the center of Jaspers’s philosophizing is the notion of the Umgreifende. Some have translated this basic notion as the “Comprehensive”; others have found the English term, the “Encompassing,” to be a more accurate rendition of the original German. The Encompassing lies beyond all horizons of determinate being, and thus never makes its appearance as a determinable object of knowledge. Like philosopher Immanuel Kant’s noumenal realm, it remains hidden behind the phenomena. Jaspers readily agrees with Kant that the Encompassing as a designation for ultimate reality is objectively unknowable. It escapes every determinate objectivity, emerging neither as a particular object nor as the totality of objects. As such, it sets the limits to the horizon of humanity’s conceptual categories. In thought, there always arises that which passes beyond thought itself. Humanity encounters the Encompassing not within a conceptual scheme but in existential decision and philosophical faith. This Encompassing appears and disappears only in its modal differentiations. The two fundamental modes of the Encompassing are the “Encompassing as being-in-itself” and the “Encompassing as being-which-we-are.” Both of these modes have their ground and animation in Existenz.

Jaspers’s concern for a clarification of the meaning and forms of being assuredly links him with the great metaphysicians of the Western tradition, and he is ready to acknowledge his debt to Plato, Aristotle, Baruch Spinoza, Hegel, and Friedrich Wilhelm Joseph Schelling. However, he differs from the classical metaphysicians in his relocation of the starting point for philosophical inquiry. Classical metaphysics has taken as its point of departure being-in-itself, conceived either as Nature, the World, or God. Jaspers approaches his program of clarification from being-which-we-are. This approach was already opened up by the critical philosophy of Kant, which remains for Jaspers the valid starting point for philosophical elucidation.

The Encompassing as being-which-we-are passes into further internally articulated structural modes. Here empirical existence (Dasein), consciousness as such (Bewusstsein überhaupt), and spirit (Geist) make their appearance. Empirical existence indicates oneself as object, by virtue of which one becomes a datum for examination by the various scientific disciplines such as biology, psychology, anthropology, and sociology. In this mode of being, one apprehends oneself simply as an object among other objects, subject to various conditioning factors. One is not yet properly known as human. One’s distinctive existential freedom has not yet been disclosed. One is simply an item particularized by...

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Existenz and Reason

All the modes of the Encompassing have their original source in Existenz. Existenz is not itself a mode, but it carries the meaning of every mode. It is the animation and the ground of all modes of the Encompassing. Thus, only in turning one’s attention to Existenz can one reach the pivotal point in Jaspers’s philosophizing. In Existenz, one reaches the abyss or the dark ground of selfhood. Existenz contains within itself an element of the irrational and thus never becomes fully transparent to consciousness as such. Consciousness is always structurally related to the universal ideas, but Existenz can never be grasped through an idea. It never becomes fully intelligible because it is the object of no science. Existenz can only be approached through concrete elucidations—hence, Jaspers’s program of Existenzerhellung. Existenz is the possibility of decision, which has its origin in time and apprehends itself only within its temporality. It escapes from every idea of consciousness as well as from the attempt of spirit to render it into an expression of a totality or a part of a whole. Existenz is the individual as historicity. It determines the individual in one’s unique past and unique future. Always moving into a future, the individual, as Existenz, is burdened with the responsibilities of decisions. This fact constitutes one’s historicity. Existenz is irreplaceable. The concrete movements within one’s historicity, which always call one to decision, disclose one in one’s unique...

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The reality of communication provides another dominant thesis in the philosophy of Jaspers. Philosophical truth, which discloses Existenz as the ground of the modes and Reason as their bond, can be grasped only in historical communication. The possibility of communication follows from the ineradicable communality of humanity. No one achieves humanity in isolation. People exist only in and through others and come to an apprehension of the truth of their Existenz through interdependent and mutual communal understanding. Truth cannot be separated from communicability. However, the truth that is expressed in communication is not simple; there are as many senses of truth as there are modes of the Encompassing being-which-we-are. In the community of one’s empirical existence, it is the pragmatic conception of truth that is valid. Empirical reality knows no absolutes that have a timeless validity. Truth in this mode is relative and changing, because empirical existence itself is in a constant process of change. That which is empirically true today may be empirically wrong tomorrow because of a new situation into which one will have passed. All empirical truth is dependent upon the context of the situation and one’s own standpoint within the situation.

As the situation perpetually changes, so does truth. At every moment, the truth of one’s standpoint is in danger of being refuted by the very fact of process. The truth in the communication of consciousness as such is logical consistency and cogent evidence. By means of logical categories, one affirms and denies that which is valid for everyone. Whereas in empirical reality, truth is relative and changing because of the multiple fractures of particulars with one another in their time-bound existence, in consciousness as such there is a self-identical consciousness that provides the condition for...

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Philosophical Logic and Faith

For Jaspers, the truth of Reason is philosophical logic; the truth of Existenz is philosophical faith. Philosophical logic and philosophical faith interpenetrate, as do Reason and Existenz themselves. Logic takes its impulse from Existenz, which it seeks to clarify. Philosophical logic is limited neither to traditional formal logic nor to mere methodology; it prevents any reduction of humanity to mere empirical existence or to a universal consciousness. Philosophical logic is negative in that it provides no new contents, but it is positive in establishing the conditions for every possible content. Philosophical faith, the truth of Existenz, confronts humanity with transcendence and discloses one’s freedom. Philosophical faith is...

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Additional Reading

Ehrlich, Leonard. Karl Jaspers: Philosophy as Faith. Amherst: University of Massachusetts Press, 1975. An analysis of Karl Jaspers’s understanding of philosophical thought as the expression of faith, in the underlying unity of the subjective and the objective, examining such key themes as the role of freedom and transcendence.

Kaufmann, Walter. From Shakespeare to Existentialism. Garden City, N.Y.: Anchor, 1960. This fine review of existentialism includes a chapter focused on Jaspers. Kaufmann’s penetrating scholarship dispels some misunderstandings of Jaspers and places him in the...

(The entire section is 281 words.)