Parmenides
Plato
Plato in Twelve Volumes, Vol. 4 translated by Harold North Fowler; Introduction by W.R.M. Lamb. Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1926.
Ceph.The one, then, might do this if it were two, and might be in two places at once; but so long as it is one, it will not?No, it will not.The one can no more touch itself than it can be two.No.Nor, again, will it touch the others.Why not?Because, as we agreed, that which is to touch anything must be outside of that which it is to touch, and next it, and there must be no third between them.True.Then there must be two, at least, if there is to be contact.There must.And if to the two a third be added in immediate succession, there will be three terms and two contacts.Yes.And thus whenever one is added, one contact also is added, and the number of contacts is always one less than the number of terms; for every succeeding number of terms exceeds the number of all the contacts just as much as the first two terms exceeded the number of their contacts. For after the first every additional term adds one to the number of contacts.Right.Then whatever the number of terms, the contacts are always one less.True.But if only one exists, and not two, there can be no contact.Of course not.We affirm that those things which are other than one are not one and do not partake of oneness, since they are other.They do not.Then there is no number in others, if one is not in them.Of course not.Then the others are neither one nor two, nor have they the name of any other number.No.The one is, then, only one, and there can be no two.That is clear.There is no contact if there are no two terms.No, there is none.Then the one does not touch the others, nor the others the one, since there is no contact.No, certainly not.Thus on all these grounds the one touches and does not touch itself and the others.So it appears.And is the one both equal and unequal to itself and the others?How is that?If the one were greater or less than the others, or, again, the others greater or less than the one, is it not true that the one, considered merely as one, and the others, considered merely as others, would be neither greater nor less than one another, so far as their own natures are concerned; but if in addition to their own natures, they both possessed equality, they would be equal to one another or if the others possessed greatness and the one smallness, or vice versa, that class to which greatness was added would be greater, and that to which smallness was added would be smaller?Certainly.