The key to an analytic understanding of Gibbon's History lies, as I have suggested, in his much neglected Essai sur l'étude de la littérature of 1758–61. Here he posited a stratified model of the historical process, separating out ‘determinate, but general causes’ – which operated in the realm of ‘manners, religion and all that comes under the yoke of opinion’ – from the superficial sphere of ‘particular causes’. Once we possess the theory of general causes, ‘it allows us to see them governing the greatness and the fall of empires’. Simple as it may sound, this was a conceptual achievement of immense significance. In the first place, the appeal to ‘determinate, but general causes’ allowed the historian to escape the snares both of rigid system building and of Pyrrhonism (that is, scepticism). Furthermore, although (as Gibbon noted) ‘no one doubts the influence of these [general] causes’, the French philosophes' deployment of manners and religion was bland, since they were not adequately related to the detailed texture of particular events. Gibbon, however, was always conscious that the concrete establishment of that relation was one of the central problems of historical writing. For example, the high political narrative might run contrary to the current of profound forces, and ‘it is when [general causes] produce their effects in the teeth of all the partial causes that one can bring into play, that they reveal themselves most strikingly’. Thus Gibbon's ideas on stratification went beyond those of the philosophes, especially Montesquieu, even if he modestly ceded to the latter the posthumous(!) honour of putting this idea into practice.