Professor Braithwaite’s inaugural lecture, here published in book form,1 is a trial run at a Platonic definition of the concept of dianemetic justice; or, as he himself would put it, a rational reconstruction of the concept “sensible-prudent-and-fair”. Aristotle left it that dianemetic justice was an equality and a matter of ratios. A just distribution of őoα µεριστ? τoς κoινωνoσι τς πoλιτείαѕ2 (Greek for “Co-operators’ Surplus”) was one in which each had an equitable share, no one having either more or less than he should. Professor Braithwaite goes further and replaces Aristotle’s ordered scale of the-more-and-the-less in which only imprecise and unhelpful answers could be given, by a numerical scale in which he can frame the question “Exactly how much is a fair share?” and propound his s own solution.