  The difficulty of this task helps to explain why Socrates takes the  curious route through the discussion of civic justice and civic  happiness. Socrates can assume that a just city is always more  successful or happy than an unjust city. The assumption begs no questions,  and Glaucon and Adeimantus readily grant it. If Socrates can then  explain how a just city is always more successful and happy than an  unjust city, by giving an account of civic justice and civic  happiness, he will have a model to propose for the relation between personal justice and flourishing.