These Cases of Conscience have spoyled the World

by these doctrines a man is taught how to be an honest thief,… and by these we may not only deceive our brother, but the law; and not the laws only, but God also.

Since their first appearance in English in the seventeenth century, the words ‘casuist’ and ‘casuistry’ have generally carried the pejorative connotation, namely ‘Subtility of wit with a chiverell conscience’; the ‘subtill distinctions of the most learned’, exploited in such a way as to make ‘foule sinnes to passe along as no sinnes’. That only ‘the Want of Conscience, makes the Case of Conscience’ became something of a commonplace; ‘Men usually set themselves to justifie what they do and love to do’, exploiting their reason in order to ‘argue and dispute in defence of those lusts which they are loath to part with’. So too in seventeenth-century French usage ‘casuiste’ and ‘casuistique’ came to imply sophistry in the service of sin, ‘des excuses à la mauvaise cupidité’, ‘raffiner’ sins out of existence, the ‘art of cavilling with God’, in Pierre Bayle's Dictionnaire historique et critique of 1696. ‘Pleaders in the court of conscience find out more distinctions and subtleties than the pleaders in the civil law-courts’, Bayle complained; morality ought instead to be the simple product of ‘good sense, and… the light which the reading of the gospel darts into the mind’.