Annas, Julia, An Introduction to Plato's Republic, Oxford: Oxford University Press, 1981.

Excerpt:

The Republic is Plato’s best-known work, and there are ways in which it is too famous for its own good. It gives us systematic answers to a whole range of questions about morality, politics, knowledge, and metaphysics, and the book is written in a way designed to sweep the reader along and give a general grasp of the way Plato sees all these questions as hanging together. So our reaction to it, at least on first reading, is likely to be over-simplified; we may feel inclined to accept or reject it as a whole, rather than coming to grips with particular arguments.

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