But I must also remind you, that the power of dialectic alone can reveal
this, and only to one who is a disciple of the previous sciences.

Of that assertion you may be as confident as of the last.

And assuredly no one will argue that there is any other method
of comprehending by any regular process all true existence or of
ascertaining what each thing is in its own nature; for the arts in
general are concerned with the desires or opinions of men, or are
cultivated with a view to production and construction, or for the
preservation of such productions and constructions; and as to the
mathematical sciences which, as we were saying, have some apprehension
of true being--geometry and the like--they only dream about being,
but never can they behold the waking reality so long as they leave the
hypotheses which they use unexamined, and are unable to give an account
of them. For when a man knows not his own first principle, and when the
conclusion and intermediate steps are also constructed out of he knows
not what, how can he imagine that such a fabric of convention can ever
become science?

Impossible, he said.

Then dialectic, and dialectic alone, goes directly to the first
principle and is the only science which does away with hypotheses in
order to make her ground secure; the eye of the soul, which is literally
buried in an outlandish slough, is by her gentle aid lifted upwards;
and she uses as handmaids and helpers in the work of conversion, the
sciences which we have been discussing. Custom terms them sciences,
but they ought to have some other name, implying greater clearness
than opinion and less clearness than science: and this, in our previous
sketch, was called understanding. But why should we dispute about names
when we have realities of such importance to consider?

Why indeed, he said, when any name will do which expresses the thought
of the mind with clearness?

At any rate, we are satisfied, as before, to have four divisions;
two for intellect and two for opinion, and to call the first division
science, the second understanding, the third belief, and the fourth
perception of shadows, opinion being concerned with becoming, and
intellect with being; and so to make a proportion:--

As being is to becoming, so is pure intellect to opinion. And as
intellect is to opinion, so is science to belief, and understanding to
the perception of shadows.

But let us defer the further correlation and subdivision of t