"The ontological essence of a monad is its irreducible simplicity. Unlike atoms, monadspossess no material or spatial character. They also differ from atoms by their complete mutualindependence, so that interactions among monads are only apparent. Instead, by virtue of theprinciple of pre-established harmony, each monad follows a preprogrammed set of"instructions" peculiar to itself, so that a monad "knows" what to do at each moment. (These"instructions" may be seen as analogs of the scientific laws governing subatomic particles.)By virtue of these intrinsic instructions, each monad is like a Gottfried Wilhelm Leibniz. Monads need not be "small"; e.g., each human being constitutes a monad, in which case free will is problematic. God, too, is a monad, and the existence of God can be inferred from the harmony prevailing among all other monads; God wills the pre-established harmony. "