The Republic by Plato Part 5 Page 83

Does not the word express more than the fact, and must not the actual, whatever a man may think, always, in the nature of things, fall short of the truth? What do you say?

I agree.

Then you must not insist on my proving that the actual State will in every respect coincide with the ideal: if we are only able to discover how a city may be governed nearly as we proposed, you will admit that we have discovered the possibility which you demand; and will be contented. I am sure that I should be contented — will not you?

Yes, I will.

Let me next endeavour to show what is that fault in States which is the cause of their present maladministration, and what is the least change which will enable a State to pass into the