For Henri Bergson, duration is not an objective mathematical unit, but the subjective perception of space-time. Bergson believed that the conventions of scientific practice were incompatible with lived experience. In his "Essay on the Immediate Data of Consciousness" (1889), Bergson argued that experience viewed as a succession of separate, thinglike states is no less an abstraction from lived consciousness than time as measured by the hands of a clock. Both are fundamentally spatial. Lived consciousness, on the other hand, is a spatiotemporal continuum, "like a mutual penetration, a solidarity, an intimate organization of elements, each of which is representative of the others and neither distinguished from nor isolated by abstracting thought." (see also memory)
For Bergson, we can describe the movement of an object in space, for example, by postulating an infinite number of reference points, through which the object may be said to move. But "they are not parts of the movement; they are so many views taken to it; they are, we say, only supposed stopping points. Never is the mobile reality in any of these points; they most we can say is that it passes through them." Bergson proposed a division of labor between the analytical methods of scientists and the intuitions of the metaphysicians, who would strive for a "true empiricism" that would seek to keep "as close to the original itself as possible."
In The Shape of Time, George Kubler relates the duration of objects to their morphology.
Following Bergson, Deleuze and Guattari describe duration as a multiplicity, like smooth space, for it cannot be divided without changing in nature at each division. (like an intensity, which is not the sum of two smaller intensities) This qualitative change is like a phase transition or emergent feature of the multiplicity. It is a "becoming." Deleuze and Guattari stress the reality specific to becoming. (see "becoming intense,") They characterize becoming as intransitive, not having an object of production other than itself. "Reality makes and remakes itself, but it is never something made." (cf immanent / transcendent)
One of the most remarkable features of the ritual process is its highly specific way of localizing duration and extension, of giving these categories names and properties, values and meanings, symptoms and legibility. (Appadurai)