[Encyclios]

Concept of time in philosophy

The concept of time differs according to whether it is considered under the objectivist aspect, in which time is seen as something real and absolute in itself, independent of relations with the external world and the human subject, or under the subjectivist-idealist view, which places the origin of time in the subject. The conception of time in contemporary existentialist thought has a separate place.

The Greek thinkers, from the Pythagoreans to Plato, had a fundamentally realist and objectivist concept of time. They saw in time the image – in movement, but a cyclic movement, always returning, as in the cycles of the years, of the seasons, of the regular movements of the stars – of the eternity and immutability of being.

In his Physics, Aristotle defines time as the “measure of movement”, that is, the measurable expression of the regular and constant movements of the life of the cosmos. Taken up in a different form by the major post-Aristotelian schools, as well as by the main thinkers of the Christian Middle Ages, this concept was however neglected by the religious thought of the late antique world.

Plotinus, in fact, identified time with the very life of the soul, with its passing from one moment to another of its inner existence; Saint Augustine, basing himself on the three-dimensionality of time, asserts that the future is “expected”, the past “remembered”, only the present is authentic temporality, even if always flowing between the other two dimensions.

The Aristotelian concept of time, however, remained dominant in philosophy until I. Kant. Kant, who instead operated a real revolution by defining time as a “pure a priori intuition”, the “form of internal sense”. Far from conceiving it as an absolute dimension, Kant sees in it rather a fundamental condition of the possibility of perception, and therefore of knowledge itself.

Now, Kant’s concept of time, interpreted in a unilateral way as in fact occurred in German idealism, undoubtedly leads to subjectivist reductions that betray the genuine thought of Kant, whose analysis of time should be integrated with those pages of the Analytic of Principles where he identifies the order of temporal succession with the causal order of phenomena: thesis proposed again in modern times by H. Reichenbach and applied also to Einstein’s theory, which always sees in time a value of causal succession, denying only the uniqueness and absoluteness of such an order.

A “conscientized” time is then again opposed to the “spatialized” time of contemporary science, in many spiritualist currents starting from H. Bergson; and also in Husserlian phenomenology, even if on a very different background, there is an interpretation of time as a current of lived experiences.

A very peculiar philosophical conception of time was born with modern existentialism, and especially with M. Heidegger, in his work entitled Being and Time. In his interpretation of “being” in terms of possibility, project and anticipation, Heidegger affirms the existential primacy of the future, in which consists that authentic temporality that the philosopher contrasts with the inauthentic temporality of datable and measurable time.