things are all.
2.bb. If one has not being, other things are not.

.....

'I cannot refuse,' said Parmenides, 'since, as Zeno remarks, we are
alone, though I may say with Ibycus, who in his old age fell in love, I,
like the old racehorse, tremble at the prospect of the course which I am
to run, and which I know so well. But as I must attempt this laborious
game, what shall be the subject? Suppose I take my own hypothesis of
the one.' 'By all means,' said Zeno. 'And who will answer me? Shall I
propose the youngest? he will be the most likely to say what he thinks,
and his answers will give me time to breathe.' 'I am the youngest,' said
Aristoteles, 'and at your service; proceed with your questions.'--The
result may be summed up as follows:--

1.a. One is not many, and therefore has no parts, and therefore is not
a whole, which is a sum of parts, and therefore has neither beginning,
middle, nor end, and is therefore unlimited, and therefore formless,
being neither round nor straight, for neither round nor straight can be
defined without assuming that they have parts; and therefore is not in
place, whether in another which would encircle and touch the one at
many points; or in itself, because that which is self-containing is also
contained, and therefore not one but two. This being premised, let us
consider whether one is capable either of motion or rest. For motion is
either change of substance, or motion on an axis, or from one place to
another. But the one is incapable of change of substance, which implies
that it ceases to be itself, or of motion on an axis, because there
would be parts around the axis; and any other motion involves change of
place. But existence in place has been already shown to be impossible;
and yet more impossible is coming into being in place, which implies
partial existence in two places at once, or entire existence neither
within nor without the same; and how can this be? And more impossible
still is the coming into being either as a whole or parts of that which
is neither a whole nor parts. The one, then, is incapable of motion.
But neither can the one be in anything, and therefore not in the same,
whether itself or some other, and is therefore incapable of rest.
Neither is one the same with itself or any other, or other than itself
or any other. For if other than itself, then other than one, and
therefore not one; and, if the same with other, it would be other, and
other than one.