The arte of logick Plainely taught in the English tongue, according to the best approued authors. Very necessary for all students in any profession, how to defend any argument against all subtill sophisters, and cauelling schismatikes, and how to confute their false syllogismes, and captious arguments. By M. Blundevile.

Of the Argument called Sorites.

WHat is Sorites?

Sorites is a kinde of Argument proceeding as it were by certaine degrees vnto the Con∣clusion, which is gathered of many Propositi∣ons necessarily following one another, and are knit together, so as the Predicate of the first Proposition is the Subiect of the second, and the Predicate of the second the Subiect of the third, and so forth euen to the last Proposition, whose Predicate being ioyned to the Subiect of the first Pro∣position, doth make the Conclusion as thus: The Soule of man doth moue it selfe: whatsoeuer moueth it selfe, is the begin∣ning of mouing: the beginning of mouing hath no end, what∣soeuer hath no end, is immortall: Ergo, the Soule of man is immortall.

When is this kinde of Argument said to be of force?

When it is made of Affirmatiue Propositions, wherein words of affinitie are necessarily ioyned together, as when kindes generall, differences, or properties, are ioyned with those speciall kindes, of whom they are spoken, or when pro∣per effects are ioyned with their proper causes, for if the Pro∣positions be eyther Negatiue, or doe not necessarily hang to∣gether, then it is no good Argument, as in Negatiues let this be your example: A Man is not a Lion, a Lion is a sensible beast: Ergo, Man is not a sensible beast. Now of Propositions not hanging necessarily together, because that proper effects are not ioyned with their proper causes, let this common iest be your example:

Whoso drinketh well, sleepeth well, Whoso sleepeth well, sinneth not, Whoso sinneth not, shall be blessed: Ergo, Whoso drinketh well, shall be blessed.

Which is no good Conclusion, for much drinke is not alwayes the cause of sleepe, nor sleeping the cause of not sin∣ning.

The Rhetoricians vse another kinde of Argument, called Gradatio, which is much like to Sorite•…•…, sauing that the Sub∣iect of the first Proposition is not rehearsed in the Conclu∣sion, for they vse it rather as an ornament of speech, then as a proofe, as the vertue of SCIPIO wanne him Fame, Fame got him Enemies, and his Enemies procured his death.