That the definition of a problem has a strong, even a determining, influence on the solution proposed is a truism acknowledged by historians more often than it is acted upon. This is partly because the empirical tradition encourages scepticism towards ‘abstract’ thought, and partly because historical enquiry inevitably becomes distanced from the pre-suppositions that launch it. This is why the conceptual foundations of substantial historical controversies require periodic inspection, especially if they have been running for a generation or more, as is the case with the debate over the ‘transition’ in nineteenth-century West Africa. At this point, readers learned in the ways of academe may already fear that they are about to be lured into one of the many deep holes that specialists dig to trap their unwary colleagues. Certainly, this debate has produced case studies that can match those generated by other historical problems in their detail and, some might say, in their obscurity too. But the wider issues ought to command wide attention: they go to the heart of the problem of the long-run economic development of Africa; they can also be set in a much broader, international context, one that encompasses European imperialism in the late nineteenth century, as this essay will try to show.

Two main kinds of conceptual reflection suggest themselves.