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 Difference, called of the Latines, Differentia.

WHat is difference?

Difference is that whereby things doe differ one from another, or any thing from it selfe.

How many kindes of differences be there?

According to Porphyrius, there be three kindes, that is to say, common, proper, and most proper or especiall, called of the La∣tines, Differentia specifica.

What call you a common difference?

A common difference is some separable accident, whereby one thing differeth from another, or from it selfe: as a hot man from a cold, or a man standing from himselfe sitting.

What is proper difference?

A proper difference is some inseparable accident, whereby one thing differeth from another, or from it selfe: as the Swanne by whitenesse differeth from the Crow, the gray-eied man from another man that hath blacke eies, or from himselfe, as hauing now an vnmoueable scarre in his face, whereas before hee had none.

What is the most proper difference?

The most proper difference, only receiued and allowed of the Logicians, is that which is spoken of many things differing in kinde or number, in asking the question what manner of thing any thing is, as this word reasonable or vnreasonable: for if I aske the question, what manner of thing this man or that man is, as Iohn, Thomas, or Richard, &c. it is rightly answered, to say, A reasonable body. Likewise if I aske what manner of thing a horse is, it is truly answered, to say, An vnreasonable body: for these be the most proper and especial differences, whereby men and bruit beasts doe differ one from another.

How manifold is the office of a Logicall difference?

Twofold: the one to diuide the generall kinde into his especi∣all kindes, and the other to constitute or make the selfe-same spe∣ciall kindes. Wherfore such differences are said in diuers respects to be sometimes diuisiue, and sometimes constitutiue, yea and sometimes both; as these differences, corporate and vncorpo∣rate, liuing and vnliuing, sensible and vnsensible, reasonable and vnreasonable; which in that they doe diuide some generall kinde into other kindes, either more speciall, or not so generall, they may be called differences diuisiue: but in that they constitute or make any speciall kinde, as this difference reasonable being ad∣ded to a sensible body, maketh the speciall kinde, man; such dif∣ference may be well called a difference constitutiue, or rather spe∣cificatiue, as the former Table of generall kindes and differences doth plainly shew.

What other diuision doe the Schoolemen make of this Logicall difference?

They say, that of these differences some do extend further then some, for some may be applied to many speciall kinds, as liuing,

and vnliuing, sensible and vnsensible, and also the difference vn∣reasonable, but the difference reasonable can be applied but to one speciall kinde onely, which is man.