  In supposing that void exists, the atomists deliberately embraced an apparent contradiction, claiming that ‘what is not’ exists.  Apparently addressing an argument by Melissus, a follower of Parmenides, the atomists paired the term for ‘nothing’ with what it negates, ‘thing,’ and claimed that—in a phrase typical of the atomists—the one ‘no more’ exists than the other (DK 67A6).  Schofield (2002) argues that this particular phrase originated with Democritus and not his teacher Leucippus.  By putting the full (or solid) and the void ontologically on a par, the atomists were apparently denying the impossibility of void.  Void they considered to be a necessary condition for local motion: if there were no unoccupied places, where could bodies move into?  Melissus had argued from the impossibility of void to the impossibility of motion; the atomists apparently reasoned in reverse, arguing from the fact that motion exists to the necessity for void space to exist (DK 67A7).  It has been suggested that Democritus' conception of void is that of the (temporarily) unfilled regions between atoms rather than a concept of absolute space (Sedley 1982). Void does not impede the motion of atoms because its essential quality is that of ‘yielding,’ in contrast to the mutual resistance of atoms.  Later atomist accounts attest that this ‘yielding’ explains the tendency of bodies to drift into emptier spaces, driven out by collision from more densely packed regions (Lucretius DRN 6.906–1089).