In traditional metaphysical philosophy, Being as Objective Subject has an essence (meaning) that is hypostatized as timeless presence; human history is therefore understood as the temporal realization of the timeless. The Objective Subject (Being) in traditional philosophy is presence, presentness—that is, something timeless, without flow and transformation (Becoming).
Kant was the first in the history of metaphysics to perceive the inner connection between Being and time. His theory of the schematism of the pure concepts of the understanding emphasizes that the understanding cannot operate independently of time, because the mediating representations, or schemata, through which the categories of thought are applied to phenomena are a priori determinations of time. Kant defines time as the time of nature or of the objective world; he treats it as a pre-existing receptacle of cosmic events, while observing that the measurement of time becomes possible only through the human soul or mind. Thus even Kant, who sensed the temporal constitution of human understanding and its relation to experience, remained bound to a conception of time inherited from the metaphysical tradition. Before Kant, as we have noted, Aristotle, in Book IV of the Physics (11, 219b1), gives time the meaning of a “natural” understanding of Being and does not inquire into the origin of time, which appears as natural motion and change. Even Husserl’s radical investigations of time, in relation to psychology and epistemology, continued to treat time as something immanent and intra-subjective. Husserl distinguishes temporal flow and the modes of consciousness through which it becomes perceptible. More specifically, in Husserl the three dimensions of time are held together within the “living present” by the transcendental ego, which is conceived as “immortal.” According to these approaches to time, the human being is situated within time. Yet the objectification of time bears the character of thematic presence: by objectifying it, we hypostatize it and turn it into a being; in effect, we attribute to it an identity that deprives it of its temporality. This is understandable within the framework of metaphysical philosophy, which conceives Being as a stable substance or essence and the Logos that apprehends it as self-determining and self-referential.
But what is the relation of Being to Non-Being, of presence to absence, of the Same to the different and the Other, of Logos to non-Logos—the “Unthought”? To investigate these questions requires the overcoming of the traditional metaphysical inheritance, which regards the World as Being intrinsically determined and representable through the conceptual-symbolic apprehensions of Logos. It also requires an opening toward That which is groundless and unthought: that which gives itself over to grounding, causal explanation, and meaning without itself being a subject or admitting predicates. It cannot be thematized or conceptually clarified. It is understood as openness “within” the horizon of time, which is becoming without a subject—temporality. The horizon of time is the Open that surrounds us, provided that “surrounds” is not understood in the sense of measurable space, but rather as the ordering and articulation of the independent parts of the World. In this sense, the horizon of time discloses the radically relational rather than substantial character of existence, as well as the interdependence of the existential determinations of particular beings that participate in the overall structure of the World.
Within the horizon of time there arises an awareness of the mortal and finite nature of the human being together with an awareness of the boundlessness of the temporal horizon. It is precisely this awareness that makes human existence transcending, since it is continually beyond itself and tends “to become what it is” (Pindar). What it is, therefore, it is not: what is passes away, while what is to come continually arrives. The transcendent element inherent in the human being is this “not yet,” the coming. In this sense, the ideal of the objectivity of Being, articulated together with its meaning or essence, is deconstructed, as is the ideal of an absolute and eternal truth associated with the timeless presence of Being. What emerges instead is the temporal-historical dimension of Being and the epochal character of truth. More precisely, we might say that Being is not: it unfolds as time together with thought, which continually opens itself to that which opens itself to thought.
Time thus becomes the possibility of understanding the World in all its forms; conversely, the World is understood in terms of time. This reveals both the temporal character of the World and the cosmic modality of time. Human existence maintains a distinctive relation to time because it is through human existence that the question of time is posed. The human being is not in time in the manner of physical objects, but “is” time. We place “is” in quotation marks in order to distinguish this claim from the conception of time as absolute and timeless presence, as eternal essence, as the permanence of a continuously existing being. The World is neither a being nor merely temporal; and time is neither merely temporal nor simply a being.
The temporality of the World and the worldliness of time constitute the enigmatic persistence of That which withholds itself, revealed in the “suddenly” of the moment—in the unexpected illumination of the coming-into-presence (closure), which continually arrives (openness) in an unending alternation. Time and World withhold themselves and constitute the “epoch” that makes possible an understanding of the historicity of thought. An “epoch” is not only what is given to us each time for thought and action and what we transform through thought and action; it is, above all, that which remains suspended and undecided, that which neither appears nor is uttered and which no judgment can formulate propositionally. In this sense, thought thinks what is given to it and, simultaneously, that which withholds itself—the unthought.
The reflective reconstruction of metaphysics and its overcoming require the opening of thought toward That which makes it possible for ordinary ontic determinations and definitions to disclose the being of beings as essence and presence, without That itself being a being. Yet it participates in the being, which means that the being is a manifestation of That: a relational structure of presence and absence, light and shadow. That which lets beings be is the radically Other in relation to all other beings; in this sense, it constitutes non-being, nothingness. This radically Other reveals itself while concealing itself through beings as a locus of participation, while beings are through their participatory relation with That.
