Abstract of Logic, Book 1 · Chapter 11 – Chapter 12
CHAP. XI. Of Genus and Species.
Ax. 1. GEnus is that which is predicated of many things, and thoſe different in Species, in the Queſtion in which it is asked, What a thing is; as, What is a Man or a Beaſt? You ſay an Animal, &c.
1. §. Genus is ſo called of that Relation or Similitude it has to that Genus or Stock of Anceſtry from whence a Generation of Men is deſcended: For as the Forefathers or Progenitors are the Beginning of their Poſterity, and their Poſterity again are in ſome kind of Relation or Kindred to each other, as proceeding from the ſaid Stock: So alſo Genus is in ſome Reſpect the Beginning of its Species, and the Species themſelves ſubject to it, agree ſo far amongſt themſelves as they are conſonting in the ſame Genus, &c.
2. §. This Definition of Genus is extant, Book 1. of the Topicks, Cap. 5. and in Porphyrie, Cap 2.
Ax. 2. Species is that which is placed under the Genus, Or that of which the Genu is predicated in the Queſtion in which it is asked What a thing is; and is ſo called from that ancient Word Specio. See from whence the Words Aſpicio, Reſpicio, &c. are derived.
Ax. 3. Of Genus's the one is the moſt general or chief, the other ſubaltern or middle.
Ax. 4. As alſo of Species's, the one of them is the moſt ſpecial or loweſt, the other Subaltern.
Ax. 5. Genus the moſt general is that which when a Genus is not a Species; or, than which there is not a ſuperiour Genus.
Ax. 6. Species, the moſt ſpecial, is that which when a Species is not a Genus, or, than which, there is no other more inferiour Species.
Ax. 7. Thoſe Genus's and Species are ſaid to be Subaltern, which interjected between the Chief Genus and Loweſt Species in reſpect of their Inferiours are ſaid to be Genus's of their Superiours Species.
1. §. But that this Subordination of Genus's and Species may the better be underſtood, be for our Example, The Category of Subſtances; in which Subſtance it ſelf is the Chief Genus; Man the loweſt Species, or moſt ſpecial. The Interjected between them, viz. between Subſtance and Man; ſuch as Animal, Living Creature, Body, &c. are Subaltern: For Animal is the Genus of Man, and Species of living Creature; and living Creature is the Genus of Animal, and Species of Body: and Body is the Species of Subſtance and Genus of living Creature, &c.
2. §. Subalterns have two Habitudes or Relations: For they are Genus's and Species with a diverſe Reſpect. The chiefeſt and loweſt have but one Habitude: For the Chief Genus is nothing elſe but a Genus, and the Loweſt Species nothing elſe but a Species. The Species may indeed be conferred either with the Genus or Individuals: For it is to the Genus ſubjected, and predicated of the Individuals; but in both of theſe Collations it is a Species: For in Reſpect of the Genus it is called a ſubjected Species; or, as they vulgarly ſay, ſubjicicible; and in Reſpect of the Individuals, a Predicated, or Predicable. And this alone conſtitutes the Second Predicable; and is thus by Porphyrie defined.
Ax. 8. A Species is that which is predicated of many different in Number in the Queſtion in which it is asked What a thing is?
1. §. For when it is asked What is Plato and Socrates? It is rightly anſwered, a Man. A Species differs from Individuals; becauſe it is predicated of many; Genus's, becauſe of thoſe things which are different in Number. Thoſe things are ſaid to be different in Number, which when of the ſame Eſſence, may be numbred as many things; as the Individuals of the ſame Species. Species alſo differs from Difference, Propriety and Accident; becauſe it is predicated in the Queſtion in which it is asked What a Thing is.
Ax. 9. Genus is alſo divided into Synonymous or Univocal, and Homonymous or Equivocal.
Ax. 10. Genus Univocal is that which is equally predicated of its Species.
Ax. 11. Equivocal, Unequally.
1. §. To be unequally predicated of its Species is nothing, elſe but to agree to one Species more; to another leſs: Or to one immediately, to the other by ſome other. And this is when one Species depends upon another. So Ens, if a Genus, is equivocal, becauſe Subſtance is more ſo than Accident. Nay, Accident is no being, any farther than as it depends upon Subſtance. But Animal is an Univocal Genus; becauſe Man is no more an Animal than a Beaſt, nor a Beaſt than a Man.
2. §. A Genus Equivocal is a Genus in an imperfect Manner.
3. §. Theſe are the Precepts uſually given in this Place concerning Genus and Species: But becauſe Ariſtotle in his Topicks delivers many, and thoſe the moſt profitable Rules, of which ſome belong to the Buſineſs of Syllogiſm, and the Ratio of finding a Medium, others to the Doctrine of ſimple Themes: Therefore it will not be beſides our Purpoſe, if out of many we ſelect the Principal of them, which appertain to the Illuſtration of ſimple Themes, and inſert them in their Places, referring the reſt to the Doctrine of Syllogiſm: And 1ſt remember that,
Ax. 12. Species partake of their Genus's, Genus's of their Species's not ſo.
1. §. foreign, that is, Participare, by the Definition of Ariſtotle in the 4th Book of Topicks, Cap. 1. where this Canon is extant, is nothing elſe but to receive the Definition of that of which it participates. But the Species receives the Definition of the Genus, but the Genus not that of the Species: For whatſoever is in the Definition of the Genus, Suppoſe Animal, that is all likewiſe included in the Definition of the Species, to wit, Man or Beaſt, but not on the contrary.
Ax. 13. The Genus is ſaid of the Species Synonymouſly, not Paronymouſly, or Denominatively: Alſo not Homonymouſly, or by way of Metaphor.
1. §. To be ſaid Synonymouſly of a thing is nothing elſe but to be ſaid as to its Name and Definition, as is before ſaid out of Ariſtotle, Cap. 5. of the Categories. But Genus is ſaid of the Species as to Name and Definition, becauſe participated of its Species. Therefore it is ſaid of Species Synonymouſly. And this is taught Book 2. of the Topicks, Cap. 2. Nor is the Genus only ſaid Synonymouſly of the Species, but alſo in the Queſtion in which it is asked, what the thing is: For all things which are anſwer'd to the Queſtion, what is it, are predicated Synonymouſly of the Species, as is aforeſaid; but cannot be rendred to the Queſtion, What is it? Paronymous thoſe things are called, which are ſaid of another as to Name only, not Definition; and that not in the Queſtion in which it is asked, what a thing is; but in which it is asked of what Quality it is; or in an Oblique Caſe. From whence follows that, that cannot be the Genus of any thing which is ſaid of it Paronymouſly. And therefore Whiteneſs is not the Genus of Snow; becauſe Snow is not ſaid to be Whiteneſs, but white. See the 4th Book of the Topicks, Cap. 1. In like manner they are ſaid to be Homonymous, under which alſo, … are contained: Or, thoſe, which, as Ariſtotle ſpeaks, are ſaid by way of Metaphor of many things, as to Name only, and not Definition: And for this Reaſon cannot be Genus's. So Dog cannot be ſaid to be the common Genus of barking Animal, and a Star; becauſe an Homonymous Word: Nor can Ardor be ſaid to be the Genus of Love; becauſe by way of Metaphor Love is ſaid to be the Ardour of Concupiſcence. See B. 4. Top. Cap. 3. which brings us to the next Axiom, viz. That,
Ax. 14. That which is the Cauſe of a thing, or Part, or Affection, or Subject, that cannot be its Genus.
1. §. This Precept is extant Book 4. Topicks, Cap. 9. and leans upon this Reaſon; viz. becauſe theſe things are all ſaid obliquely, and not in the right Caſe, or in Quid or What. So Grief, becauſe it is the Cauſe of Anger cannot be ſaid to be its Genus. In like manner Body cannot be the Genus of Animal, becauſe its Part; nor Immortality the Genus of Life Eternal, becauſe it is its Affection; nor Air of Wind, becauſe it is its Subject. For Wind is not Air moved, but the Motion of the Air, or rather, of the Airy Exhalation.
Ax. 15. Genus, and Species, are under the ſame Genus, and if Accidents, in the ſame Subject.
1. §. The firſt Member of this Precept is extant Book 4. of the Topicks, Cap. 1. the other, Cap. 5. Both of which are founded upon this Reaſon; becauſe the Genus is contained in the Species. So Will is not the true Reaſon of Juſtice; becauſe a natural Power, when Juſtice is an Habit. So Science is not the Genus of Moral Virtue; becauſe in the Intellect when Virtue is in the Appetite.
Ax. 16. The Genus is before its Species, and Species its Individual.
1. §. This Rule is delivered Book 4. of the Topicks, Cap. 2. but it is to be underſtood as to the Conſecution of the Exiſtence: For that Priority has Place here: for ſuppoſing the Species, you ſuppoſe the Genus; but not contrariwiſe. The Species therefore cannot be without its Genus; but the Genus may be without its Species's; that is, either of them, but not both together. A Synonymous Genus may be without either of them, but an Aequivocal not; but only the leſs principal. For Example; Animal may be without Man or Beaſt; but not Man and Beaſt: But Ens not without Subſtance, but only Accident. That therefore is a Genus Synonymous, this Homonymous: As alſo the Genus is towards its Species, ſo is the Species towards its Individuals.
Ax. 17. Genus is predicated of more than its Species, and the Species than its Individuals.
Ax. 18. And altho' the Species may be preſerved in one Individual, yet cannot the Genus be ſo, in one Species.
1. §. That the Genus is of greater Latitude than its Species, and the Species than its Individual, and conſequently that the Genus is predicated of more than its Species, and the Species than its Individual, follows from the Definitions of them both, and is taught by Ariſtotle Book 4. of the Topicks, Cap. 1. But that the Species may be concerned in one Individual, when the Genus, not in one Species, is from hence, becauſe the Species is more perfect in its Eſſence than the Genus, but not the Individual than its Species: For the Species includes its Genus, and beſides its Genus an Eſſential Difference: But the Individual has no Eſſential Difference added to the Species; but the Species abſolves its whole Eſſence, there being only Occaſion for Accidents, whereby it ſhould be diſcern'd from other Individuals of the ſame Species. Since therefore a Species is conſtituted by a Genus, and an Eſſential Difference, and every Difference requires a Multitude, it follows that one Species cannot conſtitute a Genus. But Individuals have no Eſſential Difference by which to diſtinguiſh them amongſt themſelves: For they agree in their whole Eſſence, and therefore no more Individuals are required for the conſtituting of a Species.
CHAP. XII. Of Difference.
Ax. 1. Difference is that by which one thing differs from another.
Ax. 2. And is either Accidental or Eſſential.
Ax. 3. Accidental is that by which all things differ by Accidents, either from other things, or themſelves.
Ax. 4. Eſſential which being added to the Genus, conſtitutes the Species, and diſtinguiſhes it Eſſentially from other Species's.
COMMENTARY.
1. §. Difference, in Greek foreign, is, with Porphyrie Threefold, Commonly, Properly, and moſt Properly ſo ſaid. Difference commonly ſo ſaid, is that by which a thing differs by a ſeparable Accident; either from another thing, as when we ſay, one Man differs from another; becauſe one ſits, the other ſtands; one is ſilent, the other ſpeaks; or, from it ſelf. So Hector ſeemed to Aencas when he appeared to him in a Dream, to differ from that Hector who returned clad with the Spoils of Achilles.
Difference properly ſo called, is that by which one thing differs from another by an inſeparable Accident or Propriety; as, a Crow from a Swan; becauſe this is white, that black. Both of theſe Differences are Accidental. The Difference moſt proper with Porphyrie, is that which we call Eſſential; as when a Man becauſe endued with Reaſon, is ſaid to differ from Brute Beaſts.
2. §. Every Difference, ſays Porphyrie, adjoined to any thing elſe, makes it to be other than it was; Accidental, that it be diſlike or other ways affected; Eſſential, that it be quite different. Whence by the Greeks they are called foreign, that is, Specifick.
Ax. 5. The Offices of Eſſential Difference are Two; to divide the Genus and conſtitute the Species.
1. §. As it divides the Genus, it is called diviſive; as it conſtitutes the Species, conſtitutive, or completive; becauſe it compleats the Definition of the Species when it is conjoined to the Genus. Difference therefore Diviſive and Conſtitutive are not two diverſe Differences, but Offices of the ſame Difference. The higheſt Genus's have no conſtitutive Difference; becauſe firſt and immediately diverſe. And the loweſt Species's have no diviſive; becauſe Individuals agree in their whole Eſſence. But Accidental Differences belong to the following Predicables; only Eſſential to this Place, and is ſo defined.
Ax. 6. Difference is that which is predicated Eſſentially of many things, different, whether in Number or Species, in the Queſtion in which it is asked, Of what Quality a thing is.
1. §. The Differences of the loweſt Species's are predicated of many things, different in Number; as, Rational, Of Plato and Socrates, &c. Thoſe of Species's Subaltern, in Species, as to be endued with Senſe of Man and Beaſt. Difference is ſaid to be predicated in the Queſtion in which it is asked, Of what Quality a thing is; becauſe it is a certain Quality of the Genus: For Genus being in its own Nature indetermined, is determined, and, as one may ſay, qualified by Difference: For to one asking, What ſort of Animal is Man? it is aptly anſwered, a Rational. Difference is ſaid to be Eſſentially predicated; becauſe put in the Definition of Species, and predicated Synonymouſly of it; that is, as to Name and Definition. And therein is Difference diſtinguiſhed from Propriety and Accident.