number, for that which has number is a whole or sum of number. These are a
few of the difficulties which are accumulating one upon another in the
consideration of being.

We may proceed now to the less exact sort of philosophers. Some of them
drag down everything to earth, and carry on a war like that of the giants,
grasping rocks and oaks in their hands. Their adversaries defend
themselves warily from an invisible world, and reduce the substances of
their opponents to the minutest fractions, until they are lost in
generation and flux. The latter sort are civil people enough; but the
materialists are rude and ignorant of dialectics; they must be taught how
to argue before they can answer. Yet, for the sake of the argument, we may
assume them to be better than they are, and able to give an account of
themselves. They admit the existence of a mortal living creature, which is
a body containing a soul, and to this they would not refuse to attribute
qualities--wisdom, folly, justice and injustice. The soul, as they say,
has a kind of body, but they do not like to assert of these qualities of
the soul, either that they are corporeal, or that they have no existence;
at this point they begin to make distinctions. 'Sons of earth,' we say to
them, 'if both visible and invisible qualities exist, what is the common
nature which is attributed to them by the term "being" or "existence"?'
And, as they are incapable of answering this question, we may as well reply
for them, that being is the power of doing or suffering. Then we turn to
the friends of ideas: to them we say, 'You distinguish becoming from
being?' 'Yes,' they will reply. 'And in becoming you participate through
the bodily senses, and in being, by thought and the mind?' 'Yes.' And you
mean by the word 'participation' a power of doing or suffering? To this
they answer--I am acquainted with them, Theaetetus, and know their ways
better than you do--that being can neither do nor suffer, though becoming
may. And we rejoin: Does not the soul know? And is not 'being' known?