There are two ways of reading the Essai which Gibbon's Memoirs inform us was written as a defence of erudition against such attacks as those of d'Alembert in the Discours préliminaire. We possess the manuscript drafts which were written at Lausanne in 1758, just before Gibbon's return to England and at Buriton later that year and in 1761; the earlier drafts include some paragraphs on the rise of Christianity which were replaced in 1761. From these, and their situation among Gibbon's other manuscripts, it is possible to draw inferences about the origin and growth of Gibbon's intentions as he wrote the Essai, inferences which may or may not coincide with what he wrote in the Memoirs thirty years later. Alternatively, we possess the printed text published in 1761, and reprinted by Lord Sheffield in the posthumous Miscellaneous Works; and this it is possible to read in the context of the print culture of the eighteenth century, juxtaposing it with d'Alembert's text and others with which it may be associated, and so arriving at conclusions regarding what Gibbon may have succeeded in saying, or in being read as saying, in the public and cosmopolitan discourse of his time as we now see it.