Certainly.

Then, in either case, the one would be made up of parts; both as being a
whole, and also as having parts?

To be sure.

And in either case, the one would be many, and not one?

True.

But, surely, it ought to be one and not many?

It ought.

Then, if the one is to remain one, it will not be a whole, and will not
have parts?

No.

But if it has no parts, it will have neither beginning, middle, nor end;
for these would of course be parts of it.

Right.

But then, again, a beginning and an end are the limits of everything?

Certainly.