The various philosophical conceptions of time with which Western culture still operates for the most part (that is, that we use in a day-to-day commonsense way and also within most empirical-seeming schemes for organizing data) were fairly well defined by about the 5th century AD. The exception is the idea of space-time in 20th-century theory of relativity.
SUMMARY: Mainly from Schreiber, with additions from Fraser and others.
Greek, Roman, and many non-western conceptions of time are cyclic and repetitive. In the work of Heraclitus, for instance, birth and death are part of an endlessly repeating cycle in the natural, as well as human, world that leaves the substance of the universe unchanged.
Many cosmological systems, such as Pythagoras's notions of number and measure, have been understood as timeless truths. In opposition, though not necessarily in contradiction, to this concept is that of ceaseless change (Heraclitus).
The Old Testament, from the very first word, "In the beginning," establishes a linear, progressive concept of time known as "salvation time" in anticipation of a messiah not yet come.
Christian salvation time demarcates human history in reference to Christ as the messiah.
Plato understood time as a product of the revolution of the celestial spheres - universal and absolute.
Aristotle, by contrast, understood time as an aspect of movement, as the numerable aspect of motion designated by "before" and "after" and quantifiable within consistent systems of measure. Time in his conception is infinite, open, and continuous.
An atomistic conception of time allows for no beginning point, and sees the future as closed.
Tense logic, or modal logic, conceives of time in terms of possibility (sometime) and necessity (always or never), thus linking time with causality.
Augustine considered time a function of human mind within which only the present was real.
Kant linked time to internal and space to external sensibility as fundamental modalities of human understanding or intuition. Time does not organize the senes, but is presupposed by them.
Newton established modern mechanics on the basis of time as an absolute, mathematical entity, "an independent variable used to describe the laws of mechanical systems."
Leibniz emphasized order relations without any objective stability.
Einstein's conceived of time as an atemporal spacetime, spatial and symmetric rather than linear and asymmetric, and of temporal relations as dependent upon frames of reference within that "block" of time.
Systems of time-keeping also embody cultural distinctions. Just a few examples are cited for the sake of demonstration: Bablyonian and Greek time-keeping marked the beginning of the day at sunrise, Egyptians marked the day from midnight to midnight, the Julian calendar starts the day at sunset, and until 1925, astronomers's clocks went from noon to noon, after which they switched to midnight as the start/end point. Nor have divisions in the days always relied upon regular intervals. A most sensible alternative was employed in medieval monastic society where the day was divided into 12 units of daylight and 12 of darkness whose dimensions varied according to seasonal cycles. (See Fraser, Time the Familiar Stranger).
Historical periodization introduces an interpretive overlay that is largely premised on a concept of time as continuous and uni-directional. Periodization schema impose ideological frameworks on temporality both by the divisions into discrete eras or epochs presumably demarcated by changes in cultural paradigms and by the use of significant events by which these divisions are marked.
SUMMARY: Herbert Bronstein, "Time Schemes, Order, and Chaos: Periodization and Ideology," (continued) Bronstein points out the ideological aspects of various conceptions used to periodize history. He begins with discussion of repetive cyclic conceptions and the implications inherent in a notion of eternal being, then addresses Judeo-Christian salvation time in which the appearance of the Messiah serves as organizing feature of all historical events, the western historian's conceptions of progress in a time scheme identifying ancient, medieval, and modern eras, and a modification of this latter in the work of Karl Jaspers, from his work, The Origin and Goal of History. Bronstein's work adds a layer of analysis that calls attention to the non-neutral character of all schema for temporal conception as an organizing interpretive frame for the description of human experience or historical events. Each of these schemes embodies a world-view, laden with a value-system and sense of progress towards or away from a culturally sanctioned goal (progress, enlightenment, salvation, rebirth, etc.)
Cross-cultural perspectives demonstrate the biases inherent in the concepts of temporality that we take to be intuitive and which serve to organize our social relations into a network of cultural activities in accord with assumptions not universally held within belief systems outside the Euro-centric perception. The relevance of such alternate perceptions to humanistic scholarship requires attention to differences in fundamental concepts of time as well as means of calculating correspondences among distinctly different time-keeping schemes. This topic will be introduced in the seminar workshop by anthropologist Ira Bashkow.
Images: from Schreiber and Bronstein