The extent to which the plain style is valued in Anglophone culture cannot be underestimated. Its basic premises (the virtues of clarity, economy and precision) are repeatedly extolled in writing manuals aimed at academics, public administrators and the general public; there are spoof awards to name and shame authors guilty of obfuscation; and special software is now available to screen compositions before they are submitted to the scrutiny of gatekeepers. However, the terms in which these injunctions are framed reveal that this is not just a practical matter: there is a whole moral and political overlay to the issue, which legitimises Plain English as the only vehicle for “truth” in the public arena, while simultaneously discrediting its rivals. This article traces the rise of Plain English from its origins in the Protestant Reformation through the Scientific Revolution and Romantic exaltation of the common man to the political populism of the present age. Deconstructing its attendant myths of transparency and authenticity, it argues that the denial of rhetoric that has consistently accompanied this discursive formation has induced a rhetorical naivety that leaves native speakers open to manipulation by professional sophists.