The Art of Logic, Book 1 · Part 26
Of a Definition.Definition, foreign.
Definition, is the unfolding, or turning out of the defined thing.
And it is either
1 Perfect.
2 Imperfect.
1 Perfect is the unfolding of the thing by essentiall terms, foreign.
The Canons hereof be five.
1 Every defined thing of perfect definition must be by it self, and directly in the predicamental order of things; so then there can be no perfect definition of doubtfull things, of Fictions, or Privations, as sin, &c. of things concrete, incompleat, &c.
2 Whatsoever is perfectly defined, is a Species.
3 A Definition must be formed perspicuous and determinate, viz. free from all ambiguity.
4 A Definition should be reciprocall and equall to the thing defined.
5 An essential Definition must consist of things simply before more known, and so indemonstrable. Not regarding what we must know, or what this or that man is able to comprehend, but absolutely and simply what is first in nature, and more known according to the Essential Order of things.
Definition hath two Notions and Conceits.
1 The one of agreement or conveniencie, called the Genus.
2 The other of distinction or difference, called the Difference.
The conceit of agreement, or Genus, both of Substances and Accidents, is found by bringing the defined thing into his predicamental Order, and by conferring with his superiours, by the Canons of a true and next Genus.
The Notion of Distinction or Difference, is either
Of Substances.
Of Accidents.
In Substances, there is one onelyonly and simple Difference, which also may easily be known by the same predicamental Table.
In Definition of Accidents, the Difference is taken from the Subject, the Efficient, the End, and Object.
The Canons of Defining Accidents by every of the Orders are nine.
1 Proper Accidents are defined by the Subject made equal, and the next efficient cause.
2 Common Accidents are defined by the mention of the efficient cause.
3 Quantity taken in general, and compleatly, is defined by mention of the subject and the efficient: as that it is … bodies Accident, arising from the extension of the matter. Special quantities, as a line, &c. are not defined, because they are things incompleat; neither is number.
4 Qualities potentiall naturall, are defined by the subject, the efficient cause, and act, unto which they are carried as to an end; As, risibility is the power of man to laugh, proceeding from a reasonable soul.
5 Habits are defined by the end & the object: as Logick is an Art directing the operations of the mind about the knowledge of things, Liberality is a vertue of taking & bestowing.
6 Qualities patible, are defined by the efficient cause, and the subject, if they be proper accidents; as colour is the quality of a mixt body, arising from the tempering together of bright and dark. Smell is an affecting quality of a mixt body, arising from the predominion of a d…y thing savouring tempered with moist.
7 Actions are defined by mention of the subject, the object, the efficient and the end; as sense is the knowledge of a sensible object, arising from the receiving of sensible species, by a fit sensory instrument, to the conservation and perfection of the living creature. Sight is a sense about Colour and light, arising from the receiving of both by their species, unto the perfection of the living Creature. Adoration is an holy operation of a Faithfull man▪ arising from the acknowledgement, and trust of God Almighty, and (in his Son) mercifull, by the holy Ghost stirred up, to the honour of God, and the faithfull mans salvation.
8 A Passion is defined by the subject, and the efficient cause; as, anger is an affection arising from heat of the blood, moved about the heart for some hu…t done. Sleep is a passion ceasing from operations in living creatures, arising from the Alimentary, nourishing and profitable humour, imbruing the brain, and as it were congealing the passages of the Animall Spirits.
9 Relations are defined by the subject relate, correlate, foundation and term.
The subject rela…e and correlate, is wherein the relation is of mutual part; some call it the materiall; as the subject of marriage, is man and woman; hereupon the Relate and Correlate is the husband and wife.
The Foundation, is, from which the relation riseth, or for which it is in the subjects: the foundation is ratio referendi, without which it would be nothing; it is answerable to the efficient cause, and is either neer or far off; as the next foundation of Marriage is the lawfull consent of each party; the far Foundation, is Gods first institution in Paradise.
The term is as the end for which the relation is brought into the subject▪ it is the office and effect of the relation; so the term of Baptisme is the seal and confirmation of the washing of sins by Christs blood; so marriage is an order or union between husband and wife, established by mutuall consent for procreation of seed, and pleasant society of life and goods.
Description foreign:
An Imperfect definition is the unfolding of a thing by terms lesse essentiall; it is called
Description: and is either.
Principal.
Lesse Principal.
Principal, which unfoldeth the thing by the Genus, and the Accidents, or the proper effects; as a man is a living Creature that can laugh, go upright, made after Gods Image.
Lesse Principal, is the unfolding of a thing by terms meerly contingent, or outward, without assigning the exact Genus, called foreign, shewing not what, but what manner a thing, it is.
And it is either. 1 Of the part of the concrete, or, 2 of the part of the thing. Of the part of the concrete, when a thing by its nature capable of a perfect definition, is yet unfolded to us unperfectly,
Of the part of the thing, when the thing it self is not capable of a perfect definition; as be all privatives, incompleat, concrete, &c.
The Canons hereof be two.
1 Privations are described by mention of the habits whose privations they are; as originall sin is an ataxie, or disorder of the understanding, will and appetite, born with us, and opposite to Gods Image.
1 Concrete accidents are not unfitly described by putting the subject in the place of the genus: as a Minister of the word is a person lawfully called and ordained to the preaching of the word, and administrating of the Sacraments. A Magistrate is a publique person, ordained of God, to rule and defend the Subjects with Justice, Prudence, and Fortitude.
Boetius gathereth from the Greeks ten forms of Descriptions
1 foreign, when the name of a thing is unfolded, as Antichrist is he that is against Christ. Justification is a reputing for Just.
2 foreign, when a thing is declared by its difference; as hatred is that which dureth longer than wrath.
3 foreign, when a thing is said to be that which it is like to; as a man is a bubble; the Church is Noahs Ark.
4 foreign, when a thing is declared by removing the contrary; as vertue is to flee vice; death is the privation of life.
5 foreign, by circumlocution; as Paul was the Teacher of the Gentiles.
6 foreign, by Example; as a substance is, for examples sake, a man, a horse, &c.
7 foreign, by want of the full of the same kinde. As an Enthymeme is that which wanteth one of the premisses to be a Syllogism.
8 foreign, by praise; as a history is the witnesse of Times, the light of Truth, the life of memory, the mistresse of life, the shower of Antiquity; also by dispraise; as riches ate the enticements to evil.
9 foreign, when one thing is said to be another, for natural similitude: as a man is a little world; wine is the soul of a Banquet.
10 foreign, by Notation; as the World is that which waxeth worse and old.