And if one has no parts, it will have neither beginning, middle, nor end; for these would be parts of one?
Right.
But then, again, a beginning and an end are the limits of everything?
Certainly.
Then the one, neither having beginning nor end, is unlimited?
Yes, unlimited.
And therefore formless, as not being able to partake either of round or straight.
How is that?
Why, the round is that of which all the extreme points are equidistant from the centre?
Yes.