Beset by the idea of space, we cannot help introducing it into our feeling of pure succession. We set states of consciousness alongside one another instead of perceiving them in one another; we picture time as a chain or a line whose parts touch without penetrating. The result feels natural — it is the time of clocks and calendars — but it has quietly replaced the thing it was meant to represent.
Bergson argues that even number presupposes space: to count moments we must hold them as distinct and simultaneous, which real succession never permits. Whenever we arrange the terms of duration in an order — before and after as points on a line — we have already converted succession into simultaneity and slipped out of time into space.
This becomes Bergson’s all-purpose diagnostic. The paradoxes of motion, the measurement of feeling, the determinist’s forces acting on the will — each, he shows, is generated by treating durational reality as if it were spread out in space. Undo the spatialization and the problem does not get solved so much as dissolved.
The theme runs throughout Time and Free Will; the projection of time into space is stated most directly in Chapter II.