This, however, is not a theme to be treated of in passing only, but will have to be discussed again and again.
And so, whether our conclusion be true or false, let us assume all this, and proceed at once from the prelude or preamble to the chief strain, and describe that in like manner.
Say, then, what is the nature and what are the divisions of dialectic, and what are the paths which lead thither; for these paths will also lead to our final rest?
Dear Glaucon, I said, you will not be able to follow me here, though I would do my best, and you should behold not an image only but the absolute truth, according to my notion.
Whether what I told you would or would not have been a reality I cannot venture to say; but you would have seen something like reality; of that I am confident.
Doubtless, he replied.
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 the subjects of opinion and of intellect, for it will be a long enquiry, many times longer than this has been.
As far as I understand, he said, I agree.
And do you also agree, I said, in describing the dialectician as one who attains a conception of the essence of each thing?
And he who does not possess and is therefore unable to impart this conception, in whatever degree he fails, may in that degree also be said to fail in intelligence?
Will you admit so much?
Yes, he said; how can I deny it?
Themes
◆Anamnesissoteriology
Platonic recollection: knowledge as the soul's recovery of what it knew before birth, with learning as remembering rather than acquisition.
The text describes dialectic as lifting the soul's 'eye' upwards from a buried slough to behold waking reality.
Augustinian and Plotinian doctrine that evil has no positive being of its own but is a lack, distortion, or absence of the good — denying ontological dualism while preserving moral seriousness.
Knowledge is framed as the absence of ignorance and error, with true being contrasted against the dream-like state of mathematics.
Diotima's staged ascent from love of beautiful bodies → beautiful souls → beautiful pursuits → beautiful knowledge → Beauty itself; the canonical scala amoris that grounds Plotinus's On the Beautiful and Bruno's Eroici Furori — distinct from generic spiritual_ascent in that eros is the specific motive force.
The passage mentions Glaucon's desire to behold the absolute truth, aligning with the motive of eros for wisdom.