 According to Aristotle’s presentation (On Generation and Corruption I 8), the motivation for the first postulation of indivisible bodies is to answer a metaphysical puzzle about the possibility of change and multiplicity. Parmenides had argued that any differentiation or change in Being implies that ‘what is not’ either is or comes to be. Although there are problems in interpreting Parmenides’ precise meaning, he was understood to have raised a problem about how change can be possible without something coming from nothing. Several Presocratics formulated, in response, philosophical systems in which change is not considered to require something coming into being from complete nonexistence, but rather the arrangement of pre-existing elements into new combinations. The atomists held that, the atoms are unchangeable and contain no internal differentiation of a sort that would allow for division.