Monad and Dyad

Leibniz' Monad is the Soul of a Body, the Unity of a Multiplicity, the experiences of which are a succession of Perceptions, each itself a Unity of a Multiplicity, driven by Appetition.  Now, a problem with this model is signified in the formulation 'the Monad is the Soul of a Body', since it suggests a separation of Monad from Body.  Furthermore, since Experience is constituted by Perceptions, the model is subject to the challenge raised by Descartes, and amplified by Phenomenalists--the supposition that the Body even exists is ungrounded, and, hence, is problematic.  But, that challenge abstracts from another dimension of Experience--Motility, the product of Volition, constituted by setting in motion multiple corporeal parts, e. g. each of the legs.  In other words, the Monad is a Formal Principle that abstracts from its complementary Material Principle, i. e. the Monad is half a Dyad.