A Literal Translation of Murray's Logic; with ... questions and answers ... by a Gentleman of this city

Front matter

A LITERAL TRANSLATION OF MURRAY'S LOGIC; WITH NUMEROUS QUESTIONS AND ANSWERS, (Towards the Explication of the intricate Parts of Logic.) DESIGNED FOR TFIE USE OF THE STUDENTS OF TRINITY COLLEGE, DUBLIN. BY A GENTLEMAN OF THIS CITY. T77* Education forms the common Mind; Juit as the Xivig is bent, the Tree's incl'm d. DUBLIN : .PRINTED BY R. MILLIKEN, GRAFTON-STREET. 1812. TO THE REV. DOCTOR USHER, FELLOW OF TRINITY COLLEGE, DUBLIN, A GENTLEMAN", WHOSE POLISHED, ELEGANT, REFINED TAST£ IS JUSTLY ESTEF.MED, AND WHOSE DEPTH OF LEARNING (more especially in this science,) IS UNIVERSALLY ALLOWED; THE FOLLOWING COMPILATION IS MOST RESPECTFULLY INSCRIBED, BY IHS MOST DEVOTED, AND MOST OBEDIENT HUMBLE SERVANT, THE AUTHOR.

Preface

. IN offering the following work to the public, I have endeavoured to adhere entirely to the ori ginal, without any adornments of my own. I have no doubt, but it may have gone through abler hands than mine, improved in its style, and further elucidations : all I pretend to is, a plain and correct translation, with some questions and answers, which the student may find useful. I don't say that I have in any way improved on the work by my alterations from other au thors : all that I have endeavoured at is concise ness ; but different tastes will doubtless receive ■different degrees of gratification from the study of either; some, whose other pursuits will per mit them, take pleasure in what is diffuse and explanatory, while others would like a work which would convey the sense of it in the short est manner.

PREFACE.

. The editor hopes, that the following pages, though they cannot confer any reputation ex cept upon the original writer, will at least be found useful, and adapted to the end proposed — the instruction and the information of youth. Dublin, 18U. ERRATA. Page 12, line 25, for incertœ, read incertoe'. Page 14, line 5, for further, read farther. Page 32, line the last, for page 14, read page 23. Page 79, line 5, a comma after in inostemivc reductions

Introduction

. Philosophy is that knowledge of things, which is attainable by the sole force of reason. Its principal parts are two ; physics, which unfolds the nature of bodies ; and ethics, which treats of imman morals. There were various opinions among the an cient philosophers of Greece, concerning both these parts, and thence innumerable disputes. Of these disputes the Greeks delighted in, in a wonderful manner, who, by defending their own tenets, aud refuting the tenets of their ad versaries, hoped the greatest praise would follow them. To assist the philosophers in this, Zeno, of Elea, invented the art of Logic, or dialects, which he divided into three parts; the first part, treating of consequences, was very obscure and useless : the second of conference; Socrates used this part; whence the Socratic method of disputing was named ; the third of disputation $ from whence most species of sophisms seem to have sprung.

Of the Socratic method and of so phisms more shall be said hereafter. After Zeno, most of the philosophers culti vated logic ; but Aristotle in particular ; he in creased the invention of his predecessors, and added many of his own : he first reduced the precepts into order, and devised the entire art : although the art of logic was begun before his time, he has been commonly esteemed as the inventor and author of the art of logic. Whether this art be really of any intrinsic use, some have doubted : but since logical terms oftentimes occur in the writings of eminent au thors, it appears altogether necessary to have these terms explained, and therefore the princi pal parts of the art itself. To do this is the de~ sign of the following compendium. Questions to the Introduction. Q. What is Philosophy ?

A. The knowledge of things attainable by the sole force of reason. Q. Why the sole force ? A. To distinguish it from the knowledge acquired by revelation. Q. Why is this definition prefixed to logic ? A. Because logic was intended for the purpose of disputing about philosophy. Q. What is knowledge ? A. The perception of the agreement or disagree ment of ideas. Q. In the definition of philosophy, which is tlie genus, and which the essential difference ? A. Notitia rerum is the genus, the rest the es sential difference. Q. Whence arises the different species of philoso phy? A. From the different subjects to which our inqui ries are directed. Q. Which are the principal parts of philosophy ? A. Physics, which unfolds the nature of bodies and ethics, which treats of the morals of men. Q. Why does he say the principal parts ?

A. Because there are other inferior kinds of plulo sophy, as metaphysics, — mathematics, — politics. Q. Why is the division of philosophy into physics and ethics, an adequate division ? A. Because physics treat of things, and ethics of action, which together comprehend all the knowledge acquired by reason. Q. What relation do physics and ethics bear to philosophy ? A. That of a species to a genus. Q. Are physics a science ? A. Xo; because their object is motion, whose essence is not known. Q. What is the end of physics ? A. The knowledge of the nature of bodies ; Q. Its objects ? A. Bodies. Q. How do philosophy and logic differ ? A. Logic is the means we make use of to acquire philosophy, which is knowledge so acquired. Q. The end of ethics ? A. The knowledge of the manners of men Q. Whence arises the necessity of logic ?

A. From the difficulty of always distinguishing truth from falsehood without the help of rules. Q. "What was the end of ancient logic ? A. Victory in dispute. Q. Its objects ? A. Consequence, — colloquy,— contention. Q. What is the difference between art and science ? A. Science consists in mere speculation, art in the mathematical means we use, to acquire any end. Q. What is meant by consequence ? A. The necessity of the conclusion which follows, and necessarily is inferred exprecedentibus. Q . What is colloquy ? A. The deduction of the conclusion from the an swers of our adversaries, refuting hi* opinion. Q. Contention ? A. Oratio acris ad confirmandum and computandum. Q. Why have some doubted of the use of ancient logic ? A. Because it consists merely of dispute and the ex plication of terms.

Part I Chap

I. Logic is the art of using reason aright, in acquiring and communicating knowledge. Its end is to investigate truth/ and to interpret the invention to others when discovered ; and therefore the operations of the understanding are its objects : of these the principal are simple apprehension, judgment and reasoning. Simple apprehension, (which is also called perception,) is the operation by which the mind receives notions. A notion (called by the moderns an idea) is the re presentation of a thing in the understanding. A word expressing a notion is called a term. Terms are either singular or universal. A singular term (which grammarians call a propel name) is that which can.be attributed to but one thing; as Socrates, Rome; and that thing is called an individual. A universal term is that which can be attributed to several things ; as a man, a city, otherwise called general, generic, common, &c. Universal terms are divided into univocal and equivocal.

A univocal term is attributed to several things in the same sense ; thus it is that the term man is attributed to Socrates, Aristotle, and all other men, in the same signification. An equivocal term is that which is attributed to a number of things in different senses : as the term dog is applied to a certain animal and to a star. Univocal terms are properly universal, but equivocal are not ; for if the same proper name (as Peter) be ap plied to several individuals, although it will be an equivocal term it will not be a universal one. A univocal term is called by the Greeks synony mous ; and a equivocal homonymous. Questions to the First Chapter. Q. What is the difference between ancient and mo? dern logic ? A. The ancient was only the art of disputing in philosophical terms ; but the modern in the art of in vestigating and communicating the truth to others, anc} treats of ideas.

Q. Why is logic called an art, not a science ? A. Because it makes use of instruments. Q. How many-fold are these instruments ? A. Four, viz. definition, division syllosism and method. Q. Unde derevatur logic ? A. vc Aoyof, which signifies reason and language, both which are necessary in logic ; the former to ac quire, the latter to communicate knowledge. Q. Why ie the word recte, used in the definition of logic ? A. Because it is done by rule. Q. What is the end of any art ? A. The point at which it aims. Q. The object? A. The means whereby we obtain the end. Q. Which are the principal operations of the mind ? A. Simple apprehension, judgment and reasoning. Q. What is the different use of these operations ? A. By simple apprehension we merely form our ideas, by judgment we discover their agreement or dis agreement with one another, and by reasoning we draw a conclusion, from the ideas we have formed.

Q. Is simple apprehension, strictly speaking, an operation ? » A. No ; for operation implies action, whereas the mind is passive in receiving ideas. Q. What is the supposed difference between notion and idea ? A. Notion is attributed to external corporeal things, and idea to internal incorporeal things. Q. Would the definition of notion do for idea ? A. No ; for the word representamen, implies a similitude, which can exist only externally, and not in the mind. Q. How are ideas divided ? A. Into simple and complex, Q. What is a simple idea ? A. One uniform conception in the mind, which can not be divided into two or more. Q. A complex ? A. That which is formed by joining two or more •imples. Q. Why are terms used in logic ? A. To express our ideas ; for logic is the art not only of acquiring, but communicating knowledge.

Q. Why is it properly called a term ? A. Because it gives bounds to our ideas, and hinders them from wandering in the mind. Q. What is the difference between the apprehension of the ancients, and perception of the moderns ? A. Apprehension refers to external objects ; per ception both to external and internal ; which last are formed, when the mind turns inward upon itself, and reflects on its own operations. Q. How do you know the first part contains only apprehension ? A. Because it treats only of simple ideas and terms. Q. Why is apprehension the first operation ? A. Because we must receive ideas before we can rea son or judge about them. Q. What is the projoer meaning of an universal terra ? A. A term which conveys a general idea to the mind. Q. How many-fold is the object of logic ? A. Two-fold, proximum and remotum ; proximum is the operations of the understanding ; remotum the ideas founded by these operations.

Q. How many-fold are individuals ? A. Two-fold, determinate, and vague : determinate. are those which are declared as existing at a certain time and place ; vague, which are expressed by a pro noun incertœ partis. Q. How many ways of determining individuals ? A. Four ; first, by a proper name ; second, by a, common appellation, which, on account of superior ex cellence, is taken for a peculiar one ; third, by a de monstrative pronoun ; fourths by a periphrasis. Q. Why is a simple idea defined to be one uni form conception in the mind, and not that which can be divided into parts ? A. Because otherwise space, duration, ike. would be included, which can be divided into parts, but are not in reality simple ideas.

Chapter II

The comprehension of a term is the aggregate of all the simpler ideas, which together perfects the notion which the term signifies. Thus the comprehension of the term man, is the aggregate of the ideas of substance, body, life, sensation and reason : for these together perfect the notion of a man. The extension of a term is the aggregate of all the individuals, of which severally that term may be predi cated ; thus of the same term man, the parts of the ex tension are Alexander, Philip, &c. , , Terms become universal, by being made the names of universal ideas ; and ideas become universal by ab straction. Abstraction is the separate consideration of some at tributes, the rest being omitted. In abstracting ideas, (that is, in making universal ideas), the mind, out of all the attributes which make up the idea of the individual, omits those that are peculiar to that individual ; but retains those that are common to it with other individuals.

For instance, the idea of any individual man is made up of the ideas of substance, body, life, sensation, reason, together with the ideas of existence in a determined place and time, of a certain countenance. Of these, the latter, (to wit, existence in a determined place and time, countenance, &c) are peculiar to that individual ; but the rest are common to him with others : if therefore omitting the latter, the former alone be retained, the idea is no longer a representation of the individual, but of all to whom the former are common, that is, of all men. This idea may be farther abstracted : for of the ideas of substance, body, life, sensation, and reason, of which the idea of a man is made up, the last alone (to wit, reason) is peculiar to man; if therefore keeping the rest, this alone be omitted, the remainder is no longer the idea of a man, but of all beings to whom the former are common, that is, of all animals.

This idea also might be further abstracted, and so on, 'till we come to the most general idea. From what has been said, it may appear, that in any abstraction of an idea the comprehension is diminished ; and that by diminishing the comprehension, the extension is increased, and vice versa. It is evident also, that if the comprehension of any idea be part of the comprehension of another, the" extension of the latter is part of the extension of the former ; and that if the comprehension of two ideas be the same, their extension also will be the same. Questions to the Second Chapter. Q. What are the affections of terms ? A. Their comprehension and extension. Q. How are terms divided as to their comprehension ? A. Into simple and complex. Q. How as to their extension ? A. Into universal and singular.

Q. How do they differ ? A. The comprehension refers to ideas ; the exten sion to individuals. Comprehension is essential to the existence of an idea, extension is not ; comprehension, cannot be diminished without altering the idea; extension can be predicated of any of its parts, comprehension cannot ; the parts of comprehension have a greater extension than their whole ; the parts of ex tension have a greater comprehension than their whole. Q. From what word in the definition of comprehension do you know this last difference ? A. Simpliciorum. Q. Why cannot we remove any of the parts of comprehension, without destroying the whole ? A. Comprehension consists of ideas ; every idea is essentially necessary to the formation of the whole ; if therefore any one of these ideas be removed, the whole aggregate would be destroyed.

Q. Why can we in extension ? A. Because it consists of individuals ; for though We remove a number of individuals, the idea continues the same, and can only be destroyed by removing all the parts. Q. Flow do we get universal terms ? A. By forming universal ideas, and making these terms their signs. Q. Why do they become universal by that ? A. Because terms originally have no meaning, and consequently vary their signification according to the idea to which they are annexed. Q. How do ideas become universal ? A. By abstraction. Q. What is logical abstraction ? A. The omitting these attributes which are peculiar to an idea, and retaining those which are common to it with other ideas. Q. What is the natural foundation of abstraction ? A. Nature and the similarity of things, from whence many individuals are. capable of being by the same ideas, which comprehend all their similar qualities, because all ideas are naturally singular, and become universal only by artificial means.

Q. What is chiefly necessary in abstraction ? A. Comparison. Q. The end of abstraction ? A. The easy communication of our ideas. Q. How does abstraction promote this end ? A. By reducing to classes those existences which are similar in their nature and riroperties: without this, we would be confined entirely to individuals, consequently form no general comparisons, or reduce any gene ral conclusion, without the excessive trouble of enume rating every individual. Q. What idea can be abstracted most ? A. An individual. Q. What idea cannot be abstracted ? A. Simple ideas, because they have no comprehension. Q. Why have they not ? A. Because all ideas .which have comprehension, are comprehended of other ideas more simple than them selves ; but a simple idea cannot be comprehended of another, nor can it have any idea more simple than itself.

Q. Why is the comprehension of a term lessened, and the extension increased by abstraction ? A. Comprehension consisting of attributes, as it is • the nature of abstraction to remove the limiting attributes of every individual, it consequeutly diminishes the comprehension, and increases the extension, be cause it takes away the attributes, which limit an idea to a certain class, and consequently renders it predicable of a greater number of individuals. Q. Can abstraction diminish the comprehension, without increasing the extension ? A. Logical abstraction cannot, but general abstraction can ; for it may omit some attributes, not peculiar, then the comprehension is lessened, and the extension not increased. Q. If the comprehension of one idea be part of the comprehension of the other, why will the extension of the latter be part of the extension of the former ?

A. If from the idea which has the greater compre hension, we abstract those ideas, by which it exceeds the other, the comprehension of both ideas, and conse quently their extension, will be the same ; but the ex tension of the idea that has greater comprehension be fore abstracted, is but a part of the idea of extension after abstraction ; and therefore a part of the exten sion of the other idea, which was proved equal to the abstracted idea. Q. If the comprehension of two ideas be the same, why should their extension be the same ? A. Because every individual possessing the comprehension of one, will possess that of the other also. Q. Why are comprehension and extension affected exactly in inverse proportion ? A. Because the greatness of comprehension depends on the number of limiting ideas, the greatness of ex tension on the removal ; therefore they are inverse pro portion, since as the one is increased, the other is di minished, and vice versa.

Q. What is the difference between abstraction and relation ? A. Abstraction compares the terms with regard to similitude only ; relation with respect to similitude and dissimilitude. B

Chapter III

There are fife classes of universal terms, which are called predicables, to wit, genus, species, difference, property, and accident. A genus is a universal term, which contains under it two or more terms, that are also universal. Thus animal is a genus, for it contains under it man and beast, which are also universal terms. A species is a universal term, which is contained under a more universal ; thus man is a species, for it is contained under anifaal, which is a more universal term. A genus is either the highest or subaltcrnum ; a species is either the lowest or subalterna. The highest genus, is that which has no genus above it. The lowest species, is that which has no species below it. Those are called subalterna genera and species, which lying between the highest genus and lowest species, are species with respect to the terms above them, and ge nera, with respect to those below them. - For instance : let substance be the highest genus, whose species are corporeal and spiritual substanc;.

Corporeal substance is therefore a species, but it may also be a genus, whose species are living and lifeless body •, living body, in like manner, may be a genus, whose species are animal and plant ; animal likewise is a genus, whose species are man and beast ; but man is the lowest species. In this series (substance, body, living body, animal, man :) the first term, substance, is the highest genus, and cannot be a species ; the last, man, is the lowest species, ami cannot be a genus ; but every intermediate term is a genus and a species. Thus animal isa genus, with respect to man, and a species with respect to liviri"hody> since every highest genus, with the terms below it, being called a category or predicament, the whole series is called a predicamental line. From what has been said above upon abstraction, it is evident that a genus is the name of a more ab stract idea, and a species, of a less abstract ; and there fore the genus has a greater extension, but the species a greater comprehension.

An essential difference is the name of the principal essential attribute, which is found in the species, but not in the genus. A property is the name of an essential attribute, not the principal, but depending on it, which is found in the species, but not in the genus. For instance ; all attributes which are in the com prehension of the genus animal, are also in die com prehension of the species man, and besides rationality, and those which depend on rationality. Rationality, therefore, is the essential difference of man ; and any attribute essentially depending on it, (as being subject to law) is a property of man . An accident is the name of an attribute not essential, which therefore the subject may have or not have without being destroyed, as whiteness in a man. Questions to the Third Chapter.

Q. Why are the classes of universal terms called predicables ? A. Because they shew how one thing may be predi cated of another. Q. What is predicable ? A. A term which may become the predicate of a proposition. Q. How many kinds of predications are there ? A. As many as there are predicables. Q. Why not as many predicables as predicates ? A. Because predicates are innumerable, and tne five predicables denote every possible relation that can exist between the predicate and subject. Q. Why must predicates be Universal ? A. Because they are ranked under predicables, which are all of them classes of universal terms. Q. Why cannot they be singular terms ? A. Because the definition of a singular is that which can be applied only to one thing, that is, to the thing for which it stands ; but to predicate any thing of it self would be absurd.

Q. Why is the genus more abstracted than the spe cies ? A. Because the definition says that the genus con tains the species under it in point of extension ; there fore it is more universal than it ; but to be more universal, it must have been more abstracted. Q. What is the difference between the genus and species, and the other predicables ? A. The genus and species are the names of things ; the other, the modes or qualities of things. Q. What term must the genus have for its subject when made the predicate of a proposition ? A. A species or individual. Q. What will the species (when it becomes the predicate of a proposition) have for its subject. A. An individual. Q. What kind of a proposition must that be which has the species for its predicate ? A. A singular. Q. How is accidens confined in predications ?

A. It can never become the predicate of an univer sal proposition. Q. What is a category ? A. A summum genus, with all its inferiors. Q. Why called a predicament ? A. Because every summum genus can be predicated of 'its inferiors or species. Q. Which of all these predicables has the greatest extension ? A. Accidens, because it is, not limited to any particular existence, but extends to many. Q. What is a subaltern genus ? A. An universal term placed between the summum genus and infima species, considered with respect to its inferior. Q. What is a subaltern species ? A. An universal placed in the same manner considered with respect to its superior. Q. What peculiar property have these infima spe cies and summum genera. A. The summum genus can only be a genus, and the infima species only a species.

Q. How do predicament and predicable differ ? A. The predicament signifies the thing predicated of, and the predicable the manner of predicating. Q. What is a predicamental line ? A. A series of genera and species down in one straight line from the summum genus to the infima species. Q. Why is it called a predicamental line ? A. Because made up of predicables. Q. Why has the genus greater extension ? A. Because more abstracted, and can be predicat ed both of a species and individual, the species of an individual only. , Q. Why has the species greater comprehension ? A. Because it contains the essential difference, which is not in the genus. Q. How do predicament and predicamental line. differ ? A. The predicamental line is one series of genera and species brought down from the summum genus, with all its inferiors.

So that there may be many pre dicamental lines in one predicament. In the predica ment all the predicamental lines are contained in one word. In the predicamental lines the ideas are extend ed to full length ; the difference is the same as between the sum total, and one of the lines to be added up in a sum of addition. Q. How can we make two predicamental lines, different in the infima species, though agreeing in every thing else ? A. By taking (when we come to the subalternate genus immediately about the infima genus) a different species of it for the infima species of each predicamental line ; so that a predicament may have as many predicamental lines as there are infima species. Q. Of what double use is the essential difference ? A. To distinguish the species from the genus, and its collateral species.

Q. Which has the species or essential difference greater extension ? A. The essential difference, because it is contained under the comprehension of the species. Q. How can we find out the summum genus of any idea ? A. By beginning with the individual, we then remove the particular attributes which distinguish that individual, and thus come to the infima species, which is the first general idea we meet. From this we ab stract the essential difference, and thus come to a sub alternate genus ; proceeding still farther in the same, we abstract the essential difference of the subalternate genera till we come to the summum genus. Q. By what method is this performed ? A. By the analytic. Q. How does Murray explain it ? A. By the analytic. Q. How can it be explained by the synthetic, which begins with a genus or whole, and proceeds to the species or its parts ?

A. There genus is here considered only as a physical or essential part of the species, though it is called an universal or logical whole ; therefore it maintains its description, beginning with the parts and proceed ing to the whole. Q. Why is not the essential difference found in the genus ? A. Because it is the chief distinguishing quality of the species. Q. How many species can a genus have ? A. As many as there are universal ideas under it, different from each other in some essential point. Q. Why are there so many more species than gene ra ? A. Because many species are contained under one genus. Q. How do the essential difference and proprium differ from the accidens ? A. The two former cannot be separated from the subject — the latter can. Q. Why should the accidens be predicated parti cularly ? A. If it was predicated universally, it would be an essential attribute.

Chapter IV

The ancient philosophers reduced all things to certain classes, and professed to explain the nature of each class, in the hope that the nature and mutual relation of the things themselves might thence be dis cerned. They fixed on ten such classes, and called those categories or predicaments ; each category con tains one summum genus, with its inferiors, and there fore is defined a series of things, disposed gradually uatf der the same highest genus. Since therefore the number of categories being ar- , bitrary, and the doctrine of little use, let it suffice briefly to recite their names. I. Substance, which is a thing subsisting by itself, that is, which can exist without the existence of any other thing to inhere in. II. Quantity, of which there are three species ; number, time, and magnitude.