The Cambridge History of English and American Literature in 18 Volumes (1907–21). Volume VII. Cavalier and Puritan. XII. Hobbes and Contemporary Philosophy. § 5. The Casuists. The doctrine of a law of nature was commonly relied upon by the more philosophical writers who dealt with the details of moral duty. Among the moralists of this class may be reckoned William Perkins, author of Armilla aurea (1590) (Englished as A Golden Chaine, 1600), and of The Whole Treatise of the Cases of Conscience (1608); William Ames, a Calvinistic theologian, who wrote De Conscientia et ejus jure vel casibus (1630); and Robert Sanderson, bishop of Lincoln, who wrote not only a Latin compendium of logic (Oxford, 1615), but many works besides, including De juramenti promissorii obligatione (1647), and De obligatione conscientiae. The former of these is said to have been translated into English by king Charles during his imprisonment. Joseph Hall, bishop of Norwich and satirist, was the author of Characters of Vertues and Vices (1608) and of Decisions of diverse Practicall Cases of Conscience (1649). But the greatest work of the kind in English, and, perhaps, the greatest treatise on casuistry ever written by a protestant theologian, is the Ductor Dubitantium of Jeremy Taylor (1660). Publishing shortly after the restoration, and dedicating his book to the king, the author rejoices that “now our duty stands on the sunny side.” He professes to open out a way untrodden before. He will not collect individual cases of conscience, for they are infinite; but he seeks to provide a “general instrument of moral theology, by the rules and measures of which the guides of souls may determine the particulars that shall be brought before them.” The work opens with a description of conscience as a reflection of the divine law—“the brightness and splendour of the eternal light, a spotless mirror of the divine majesty, and the image of the goodness of God.” It proceeds to describe the characteristics of individual consciences when brought into contact with the problems of conduct; it passes on to an enquiry into the nature of law in general and of particular laws, divine and human; and it closes with a discussion of the nature and causes of good and evil. The whole forms a comprehensive treatise on Christian ethics, based, undoubtedly, on traditional scholastic doctrines, but holding firmly to the inwardness of morality, and illustrated by an extraordinary wealth of concrete examples.   6