Monthly Archives: August 2015

Categories of Argument

John Tillotson (1630—1694) was an interesting person.  Born in Yorkshire in 1630, son of a Puritan clothier, he went up to Cambridge in 1647, graduating BA in 1650, MA in 1654, and becoming a fellow of Clare College.  Tillotson married the stepdaughter of John Wilkins (incidentally, Oliver Cromwell’s niece) and Wilkins and Tillotson became very close.  Wilkins got Tillotson elected Fellow of the Royal Society, and Tillotson was appointed Wilkins’ literary executor after Wilkins’ death in 1672. Meanwhile, Tillotson was marching up the ranks of the Church of England collecting plum positions and ending up as the Archbishop of Canterbury.

Tillotson published a number of his sermons during has lifetime and after his death, both previously published and unpublished sermons were collected, edited, and published in numerous editions, typically running around 12 or 14 volumes. They were extremely popular among both clergy and lay-people and circulated widely for over a century. In the first sermon in the collected editions (this quote is from the 1748 Edinburgh edition), he lays out a four-fold system of argument, breaking knowledge into mathematical, natural philosophical, and moral realms, as well as matters of fact, in which I think he gives a very clear exposition of epistemology in the late 17th century (he disclaims originality in the classification, but gives a good exposition).

Mathematical things, being of an abstracted nature, are capable of the clearest and strictest demonstration: but conclusions in natural philosophy, are capable of proof by an induction of experiments; things of a moral nature, by moral arguments; and matters of fact, by credible testimony. And though none of these be capable of that strict kind of demonstration which mathematical matters are; yet have we an undoubted assurance of them, when they are proved by the best arguments that things of that kind will bear. No man can demonstrate to me, unless we will call every argument that is fit to convince a wise man a demonstration, that there is such an island in America as Jamaica: yet, upon the testimony of credible persons who have seen it, and authors who have written of it, I am as free from all doubt concerning it, as I am from doubting of the clearest mathematical demonstration. So that this is to be entertained as a form principle, by all those who pretend to be certain of any thing at all, That when any thing, in any of these kinds, is proved by as good arguments as a thing of that kind is capable of, and we have as great assurance that it is, as we could possibly have supposing it were, we ought not in reason to make any doubt of the existence of that thing.

There’s more. In fact there are 254 more sermons, and this one alone runs 55 pages. Enjoy.