young Aristoteles (later a member of the Thirty Tyrants, not to be confused with Plato's eventual student Aristotle), takes the place of Socrates as Parmenides' interlocutor. Discussion with Aristoteles This difficult second part of the dialogue is generally agreed to be one of the most challenging, and sometimes bizarre, pieces in the whole of the Platonic corpus. It consists of an unrelenting series of difficult and subtle arguments, where the exchange is stripped of all but the bare essentials of the arguments involved. Gone are the drama and colour we are accustomed to from earlier dialogues. The second part of the dialogue can be divided thus: Hypothesis/Deduction n. 1 (137c-142a): If it is one. The one cannot be made up of parts, because then the one would be made of many. Nor can it be a whole, because wholes are made of parts. Thus the one has no parts and is not a whole. It has not a beginning, a middle nor an end because these are parts, it is therefore unlimited. It has no shape because it is neither linear nor circular: a circle has parts all equidistant from the centre, but the one has no parts nor a centre; It is not a line because a line has a middle and two extremes, which the one cannot have. Thus the one has no shape. The one cannot be in anything nor in itself. If it was in another it would be all surrounded and by what it is inside and would be touched at many parts by what contains it, but the one has no parts and thus cannot be inside something else. If it were in itself it would contain itself, but if it is contained then it is different from what contains it and thus the one would be two. The one cannot move because movement is change or change in position. It cannot change because it has no parts to change. If it moves position it moves either circularly or linearly. If it spins in place its outer part revolves around its middle but the one has neither. If it moves its position it moves through something else, which it cannot be inside. Thus the one does not move. The one must be itself and cannot be different from it. The one does not take part in the flowing of time so it is imperishable.