Abstract
In 1943 one of the authors of this paper set out a case for the view that the sixth book of Polybius' Histories contained two layers, written at different times, and indicating a change in the historian's assessment of the achievements and merits of the Roman hegemony. The arguments there put forward met with some acceptance; but the recent burst of interest in the problems of the sixth book has shown that unanimity is still remote. Among scholars writing since 1943, one, G. B. Cardona, is a ‘separatist’ who accepts the views of De Sanctis; another, W. Theiler, believes that three ‘layers’ of composition can be detected and isolated; three, E. Mioni, H. Erbse, and H. Ryffel, are ‘Unitarians’, but vary in the date they assign to the composition of the Histories; and K. Ziegler in his R.E. article on Polybius argues for composition in the sixties followed by a revision and publication before 146