In contrast to the archetypal model of the "tenor foundation," ars nova motets often present many isorhythmic inconsistencies between the upper and lower voices. Some of these structural divergences in Machaut's motets, however, seem to result from a compositional process initially based on a common arrangement of the voices. In order to discover this, it is necessary to move away from the isorhythm and examine the only musical data that are strictly periodic. These elements are the voice rests - pauses - which fragment the polyphony into many sections into which the musical discourse is divided. In principle, the rests of the upper voices follow an arrangement similar to that of the tenor, with the only difference that their respective positions are constantly shifted so that no rests are superimposed. rests are superimposed. On the one hand, this arrangement consequently encourages a reassessment of the structural involvement of the tenor in the upper voices. On the other hand, the systematic shifting of the rests invites us to consider the periodicity of the motet, which, far from being linear, is based on a circular conception of the temporal framework: music of repetition, the motet is, from its genesis, subjected to the dynamics of a circle, the rotations of which meticulously organize the polyphonic hierarchy like ingenious gears.