The previous chapter considered a puritan who preached a prudent charity and found theological opponents wherever he went. Here we consider a latitudinarian who preached a Christianized prudence and found friends in diametrically opposed camps. John Wilkins was an exemplary latitude-man, whose ethic of hospitality found its way into both his life and writings. He valued temperance in judgement and possessed a spirit of open-minded inquiry that has left an impression on succeeding ages. Following Aristotle, Wilkins observes in the opening chapters of his Of the Principles and Duties of Natural Religion, ‘Now where the Excess and Defect do make Vices, or such things as ought not to be, there the Mediocrity must denote something that ought to be, and consequently must be a Virtue, and have in it the obligation of Duty’. ‘Mediocrity’ in this non-pejorative sense is the defining characteristic of Wilkins as a person and as a natural theologian: his Principles and Duties was published at the chronological midpoint of our fifty-year window of enquiry, in 1675, and it occupies a middle position on the methodological and theological debates that so diversified seventeenth-century natural theologies. He strikes a compromise between veneration of ancient texts and new experimentalism, between deductive and empirical modes of reasoning, between miracles and natural law, and between human reason and the authority of scripture.