Leucippus conceded to the Monists that there could be no motion without a void. The result is a theory which he states as follows: The void is not-being, and no part of what is is not-being; for what is in the strict sense of the term is an absolute plenum. This plenum, however, is not one; on the contrary, it is a many infinite in number and invisible owing to the minuteness of their bulk. The many move in the void for there is a void: and by coming together they produce coming-to-be, while by separating they provide passing-away. Moreover, they act and suffer action whenever they chance to be in contact for there they are not one, and they generate by being put together and becoming intertwined. From the genuinely one, on the other hand, there could never have come to be a multiplicity, nor from the genuinely many a one; that is impossible.p. 68.

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