BERGSON S CONCEPTION OF DXJRATION 197 



we feel it as a quality. "That our ordinary conception of duration 



depends on a gradual incursion of space into the domain of pure 



consciousness is proved by the fact that in order to deprive the ego 



of the faculty of perceiving a homogeneous time it is enough to 



take away from it this outer circle of psychic states which it uses as 



a balance-wheel." Sleep alters the communicating surface of the 



ego because the organic functions are relaxed, and here we no longer 



measure duration, we feel it; it becomes a quahty instead of a 



quantity. Bergson believes that through daily experience we ought 



to be able to distinguish between the real duration of quality, which 



is probably what animals perceive, and time materiaHzed, which has 



become quantity by being set out in space. For instance, sometimes 



we do not notice the number of strokes of a distant 



ura ion a dock until several have sounded and we find that they 



Musical Phrase , •' 



have melted into one another instead of being set out 



side by side, like a musical phrase. In reconstructing this phrase, 



our imagination makes one, two, or three strokes, but our feeHngs 



say that the total ejfect was qualitatively different, and we feel that four 



was the number of strokes sounded. In its own way, the mind had 



ascertained the number of strokes and not by a process of addition or 



juxtaposition. "In a word, the number of strokes was perceived as 



a quahty and not as a quantity: it is thus that duration is presented 



to immediate consciousness, and it retains this form so long as it 



does not give place to a symbolical representation derived from 



extensity." 



Thus we should distinguish two kinds of multiphcity and two very 



different kinds of duration. There is the homogeneous duration, 



the extensive symbol of duration; and there is the heterogeneous 



duration, whose moments permeate each other. Likewise there is 



the numerical multiplicity of conscious states and a quahtative 



multiphcity: the self with well-defined states, and the self whose 



succeeding states melt into each other. We can expect, then, every 



conscious state to assume a different aspect, according as we consider 



it within a discreet multiphcity or a confused multiphcity, in time 



as quantity or time as quahty. The fleeting duration of our ego is 



