In the eighteenth century, most Scottish Protestants took it for granted that Roman Catholicism was antithetical to the spirit of “this enlightened age.” Amid the several polarities that framed their social theory—barbarism and politeness, superstition and rational enquiry, feudal and commercial, Highland and Lowland—popery in every case stood with the first term and Protestantism with the second. Sir Walter Scott's Redgauntlet, set in the 1760s, is redolent of these contrarieties. He draws a stark contrast between the world of Darsie Latimer, the cosmopolitan, bourgeois, and Presbyterian world of an Edinburgh attorney, and the world of Hugh Redgauntlet, rugged and rude, clannish and popish. When the Stuart Pretender appears on the scene he is disguised as a prelate, his odor more of sinister hegemony than of pious sanctimony. Scott's tableau captured the Enlightenment commonplace that the purblind faith of popery was a spiritual halter by which the credulous were led into political despotism. Catholicism, by its treasonable Jacobitism and its mendacious superstition, seemed self-exiled from the royal road of Scottish civil and intellectual improvement.
It is not too harsh to suggest that modern scholarship on the Scottish Enlightenment has implicitly endorsed this view, for next to nothing has been written about the intellectual history of Scottish Catholicism, let alone anything comparable with the two full-scale studies now available on the English Catholic Enlightenment. One historian has suggested an alternative view, by suggesting that, in the emergence of the Scottish Enlightenment, it was Catholics and Episcopalians who, as alienated outsiders, helped loosen the straitjacket of Calvinist orthodoxy.