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 Argumentation, and of the foure kindes thereof in gene∣rall, and also of the first Principles of a Syllogisme.

HAuing hitherto sufficiently spoken of words both simple and compound, whereof all que∣stions doe consist, also of definition and di∣uision, of Method, of Propositions, and of the places: It resteth now that I declare vnto you the formes and kinds of reasoning called Argumentatiō, which be the means whereby in all compound questions the trueth may bee discerned from falshood, wherein consisteth the chiefest fruit of Logicke: and therefore you shal vnderstand that there be foure principal kinds or formes of Ar∣gumentation, (that is) a Syllogisme, an Induction, an Ethymeme, and Example, I say here principall, because there be diuers other formes which though they be not so necessary, yet I will briesly treat of them hereafter: But for so much as the Syllogisme is the chiefest, whereunto all others are reserred as things vnperfect, vnto a thing perfect, I wil first speake of a Syllogisme, and of all the parts thereof: but yet before I define or diuide a Syllogisme, I thinke it very ne∣cessary to declare vnto you the first Principles aswell Materiall, as Regular, of a simple Syllogisme consisting of simple Propositions.

Which call you Materiall Principles?

Materiall Principles are three simple Propositions, and three termes, (that is to say) the Subiect, the Predicate, and the meane terme hereafter defined, whereof the Subiect and the Predicate are said to be the outermost limits or bounds of any simple Proposition.

Why are they called Termes or limits?

Because they limite a Proposition, euen as Dole-stones or Meares doe limite a piece of ground in the field, and be the vt∣termost parts or bounds whereunto any Proposition is to bee resolued, as for example in this Proposition, euery man is a sensible body: these two words, man, and sensible body, are the termes, limits, or bounds, whereof as the said Proposition is compounded, so into the same it is to be resolued, as into his vttermost parts that haue any signification: for letters and sillables of themselues be without signification, and therefore can limite no speach, so that the termes of Propositions must be either Nounes, or Verbes, which be onely voices significa∣tiue, as haue been said before.

Which be the Principles regulatiue?

The Principles regulatiue of a Syllogisme bee these two phrases of speach, to bee spoken of all, and to bee spoken of none.

What is to be spoken of all?

That is, when the predicate being truly spoken of the Sub∣iect, must needs be also spoken of all that is comprehended vn∣der the said subiect: as when I say euery man is a sensible body: here this word sensible body, is not only spoken of man in ge∣nerall, but also of Peter and Iohn, and of euery other man in particular, comprehended vnder the foresaid Subiect, man.

What is to be spoken of none?

It is when the Predicate being denied to be spoken of the Subiect, is denied also to bee spoken of any thing contained in the Subiect: as when I say no man is a stone, here like as this word stone is denied to be spoken of man, so it is also denied to be spoken of Peter and Iohn, & of euery other singular man: out of which Definitions are gathered two necessary rules.

Which be they?

The first rule is, whatsoeuer is truely affirmed of his naturall and proper Subiect, is also affirmed of all those things which are contained vnder the said Subiect: the second rule is thus, whatsoeuer is denied to bee spoken of any Subiect, is also de∣nied to bee spoken of euery thing contained vnder the said Subiect.

Whereto serue these rules?

The first rule confirmeth all Syllogismes affirmatiue, and the second confirmeth all Syllogismes negatiue.