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Abstrait of a Trealise, entitled, LOGIC; or, The Art of discovering TRUTH.

Written in French by Father REGNAULT. OGIC is a science convenient for all sorts of persons, and of use on L

almost all occasions of life. There are a thousand things of which we may safely be ignorant, but it is of utmost importance to acquire a juftness in our thoughts, in our judgments, and ratiocinations. And as the end of this art is to preserve from error, and to teach how to discover truth, it must be acknowledg'd to be of infinite advantage in all conditions of life. The greatest part of mankind are unhappy only by forming falle ideas of objects, judging erroneously, and reasoning absurdly concerning them, and the happiness of others often depends on nothing but the justness of their thoughts and reflexions. We too commonly ascribe a great part of the calamities which befall us to our evil fortune, tho' they have no other source than our false judgment. The happy success of an enterprize, if not crossed by some unforeseen event, muft naturally depend on the juft measures which are taken, and we never cake such measures but in consequence of those ideas which we form of the nature of that enterprize. Self-love induces us to impute to chance and fortune, those ill events which we ought to ascribe wholly to our own defect of judgment, or want of discernment. Chance is a phantom,which we endeavour to realise, in order to discharge ourselves of those faults which we commit.

All men are endu'd with a kind of Logic, tho' too imperfect to preferve them from error. And here it is that art comes in very seasonably to the assistance of nature, by directing the mind in the right way for the discovery of truth. This subject has been treated of more than once by great men, but not exhausted; it is a field of too vast extent to fall within known limits. Some reflexions on what passes before our eyes in the ordinary course of affairs, and within ourselves at the moment when we think, induced father Regnault to form a design of adding some new degree of perfection to this art. This work is in the taste of his Physical Dialogues between Arijus and Eudoxus, who are also the persons introduced as talkers in this piece. Some new notions, together with some more antient, but vary'd, and set in a new light, are capable of awakening the attention of the reader. We love now more than ever variety in things, and in the manner in which they are represented to the underftanding.

His Logic has one great advantage, in that it is adapted to the capacity of all sorts of people. A young person, who has had but a small taste of learning, may understand it without the help of a master. The author has designedly avoided 10 burden it with a great number of rules, which rather fatigue than enlighten the understanding; he uses none but such as appear to be calculated for a book of common use, and rejects all subtilties, which are rather ingenious than useful. In thus confining himself to what is fimply necessary, he has comprehended in one moderate vo


Tume the best part

of what is contain'd in all the books written upon the Tubject.

There are in every science certain terms, of no use in the common affairs of life. Those which our author thought were necessary to be us fed, he explains with much clearness and precision. An excessive delicacy is too ape to disdain such expressions as are unsuited to it, or offenfive to the ear; and they might indeed be rejected, but 'twere better to retain them, to know their signification, their force, and their value, that we may be in a condition to perceive the truth in good works, and to discover error in such as are of a pernicious tendency.

Rules are not always sufficient for the understanding of truth, there is frequent need of examples, and of such too as are well chofen. Our author furnishes us with a good number of examples in his Logic, which befi des has its maxims, and practical reflexions under proper heads, or, to say all in a word, its method, which is extensive, and of general use. In this meihod we are shown the path by which we must arrive at diitant truths in. proceeding step after step by degrees, sometimes from more simple and easy truths to those of a more difficult and complex nature, and sometimes in a contrary order, but always from known truths to unknown. We here learn what truths are most important in the discovery, the difficulties which attend it, and the way to surmount then, the art of informing ourselves, and instructing others, of letting a question in a proper light, of exciting a cariofity of mind, and keeping it attentive, how to move concern, to act the critic without offence, to dispute to good effect, and even to write for the interest of truth.

The independent strokes, and digreffive passages which occur here and there in this conversation between Aristus and Eudoxus are very proper to dispel that dulness and weariness, which are the ordinary effects of a dry and abstracted subject. They are a kind of general meditations, in which the mind reflecting on the passions of the heart, on the impre! fions from external objects, and on what passes within itself when it perceives, judges, or ratiocinates, discovers the marks of the different forts of ideas, with the rules or laws of which they are susceptible, in order to render them juft, clear, true and distinct. Aritus is a young man of a penetrating wit, and a happy memory, has a taste for the sciences, with an ardent desire to learn the secret of finding out the truth. Eudoxus is the person who undertakes to teach him this secret.–Ariffus, being in some fort engaged in meditations with Eudoxus, discovers from his own manner of thinking the way to think justly. When he is thus led into the right method by Eudoxus, he makes dilcoveries from time to time himself of truths, of which beofre he had only received hints from Eudoxus, the confident of his reflections, and constant witness of his researches, and has the pleasure of being able to ascribe to himielt some merit in the discoveries which he makes, In this manner they both proceed as it were in concert to the very source of our errors, in order to find a preservative against the.n.

There are twelve of these dialogues, and their subjeéts are as follows. The first treats of Logic in general; ihe second, of the properties of ideas ; the third, of rules relating to ideas; the fourth, of the exprefions of ideas. The fifth dialogue concerns the properties of judgment; the fixth is on the different kinds of propositions ; the feventh relates to


propofitions compared one with another; the eighth, to the rules or laws of judgment; the ninth is on the sources of false judgment. The tenth has for its subject the properties of ratiocination ; the eleventh its laws; and the last dialogue is upon method.

The first is very short; it begins with some instances of the clearest truths, which frequently, go by the name of first principles or axioms. When you say what is, is, you speak a truth, and at the same time a truth the most simple, clear and intelligible, because we readily conceive that it is impossible for a thing to be and not to be at the same time. These sorts of truths are easily discover'd, but there are others more difficult to be understood, and not discoverable but by a particular direction of the operations of the mind, which is the subject of the rest of this dialogue.

In the second, the author first explains, in a very clear manner, the terms obje&t, perception, sensation, imagination, inward sentiment or consciousness, attention and idea. In all these he is very distinct and particular, and illustrates what he says with a great number of examples. To form a notion of the argument and method of this dialogue, take the following short abstract.

Logic is the art of discovering truth. Truth is discover'd by the operations of the mind. The first operation of the mind is perception, or an idea. An iden, or perception, is a simple view, a nocion, which neither affirms nor denies, nor determines any thing. I see a flower, I think on God, without determining any thing concerning the divine nature and perfections, or concerning the flower ; this is perception. Accord. ing to the different objects, or different manner of perceiving, Perception is distinguished into sensation, imagination, sentiment, consciousness, attention and idea. Sensation is when we perceive the sensible qualities of bodies, by the present action of outward objects upon the senses. Imagination is when we perceive these sensible qualities, without the present ac. tion of external objects upon the senses. Sentiment is when we experience within ourselves some affection, some passion; for instance, joy, or sadness. Consciousness is when we have a knowledge of the existence of the modes of our soul, of its affections, its passions, and its though:s, without knowing the nature or properties, in such a manner as to be able clearly to explain ourselves upon the subject. Attention is a strong and constant perception; and idea is when we have a conception of the nature and properties of things, so as to be able clearly to unfold and explain them. To illustrate the same by examples in each operation : The sight of a blue firmament, bespangled with ftare, is sensation ; the remembrance of a spectacle, imagination ; joy or sorrow, sentiment; the knowledge of our sentiments, imaginations, &c. consciousness, or incvard sentiment; the constant view of a danger which threatens us, or of something good which concerns us, and which we expect, attention ; the idea of God, justice, the number four, fix, idea in its proper sense. There is an idea of substance, and an idea of mode. Here the author gives us a definition of substance, and mode. The essence, fature, and foundation of every thing is the object of a pure idea, or idea taken in its proper sense. So.netimes it is a singular idea, or such as presents to the mind a single, determinate, fixed object, as the idea of Eudoxus; sometimes it is an univerfal idea, or what agrees to several objects, both in general and particular, as the idea of a flower, which agrees indifferently to all flowers, and to the Anemone, Jonquil, Tulip and Amaranthus in particular,

A fingular idea contains universal ideas, which upon examination disclose themselves; and these universal ideas comprehend others more general than themselves. Thus from the idea of Eudoxus arises the idea of man, from that of man the idea of animal, whence we have the idea of being, which is a barren idea productive of nothing farther. The idea then of being alone is simple properly speaking, the others are complex. These complex ideas have their proper foundation and extent. The foundation of a complex idea is the conjunction of the ideas comprehended under it ; as the collection of the feveral ideas of rational, animal, substance, &c. is the foundation of the idea of man. The extent of an idea is its relation to individuals ; thus the extent of the idea of man is the relation of that idea to Aristus, Eudoxus, &c. Several complex ideas discover to us several perfections in the same object. The general ideas, with relation to the different perfections which display themselves in the same object, are the genus, species, difference, property and accident. The most general of these ideas is that of genus ; that of species is less general; an idea which limits or determines the genus to such a species is a difference ; an idea of a perfection which is essential, or arising from the fundamental conftitution of the species is a property, and the idea of an accidental quality an accident. We give the same names to the different objects of these ideas. Of ideas, whether general or not general, some are abfolate, others relative. The former prefent only their bare object to the mind, as the idea of a circle ; the other excite other ideas, as the idea of a creature raises in the mind the idea of a creator ; the former appears folitary and alone, the other always in company,

Different kinds of ideas have different properties and qualities, as some are clear, others obscure, fome true, others false, fome lively, others faint, some distinct, others confus’d. Clear ideas discover to the mind the most inward parts of their object, or its very nature, which obscure ideas fail of doing. True ideas represent their object such as it really is; false ideas thew it with such properties as belong not to it. Lively ideas strongly attract the attention of the mind to their ob. ject ; faint ideas scarcely attract at all, or are incapable of fixing the attention. Distinct ideas exhibit their object clearly and easily distinguishable from others ; confused, on the contrary, represent the same in a disorderly and indistinct manner.

We have given you the substance of the ad dialogue : In the 3d the author gives us rules which may be hly serviceable to us for obtaining such ideas as are clear, just, regular, proper, true, and free from illufion. It is not only requir'd to have these ideas, but to know how to express them by words, when we would make ourselves understood; these words, or terms, which are in use among Logicians, are the subje&t of the 4th dialogue.

The design of the sth is to explain the nature, with the different kitis and properties of judgment, which our author defines a determination of the mind on the relation which it perceives between the chjects of its ideas. Three things therefore are to be confider'd in judgmeat.


1. The

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1. The ideas in the mind, which are two at least ; 2. The compa: rison of those ideas ; 3. The perception of some relation of agreement or disagreement in their objects ; which is succeeded by a determination.

If it be here asked, whether judgment be the perception itself of the relation ; in answer to this question it is sufficient to reflect on what passes within us, when we form a judgment or determination. The person who determines is fenfible that his mind adds something to perception, and even that a relation may be perceiv'd on which no judg. ment may pass at all. Two persons see a-far off a square tower ; it appears round to both, because of the distance. One of them, who never saw it near, judges it to be round by the appearance ; the other, who has seen it neas, and knows it is square, does not judge it to be round; otherwise he would judge it to be round and not round at the fame time. Judgment therefore is not perception itself, but fupposes it, and is a kind of second thought, in which we affirm or deny the relation of the object of one idea to the object of another idea. Hence there are two forts of judgment; one affirmative, by which we affirm, as when we say God is juft; the other negative, by which we deny, as when it it said God is no deceiver.

The fixth dialogue treats of the different kinds of propositions, and is naturally consequent from the former, for there is no judgment with out a proposition. This dialogue is hardly capable of an extract; it contains too many particulars, and, what is more, such particulars as form a chain which cannot well be broken. The same may be said of the seventh, in which the author compares together the different kinds of propofitions. The comparison is well connected, and it is hard to fay whether the reader has most realon to be pleased with Aristus or Eudoxus, who both of thers acquit themselves perfetly well of their respective parts. In the eighth dialogue, which concerns the rules or laws of judgment, we meet with very judicious remarks on definitions, and the relation of ideas to one another, of excellent use in all sciences.

There is perhaps nothing which deserves to be more regarded than the precepts in the ninth dialogue, in which the author exposes the sources of false judgment. These sources are not far distant from us.

We must search for them in ourselves, and in our neighbourhood. · They may be found in impatience, sloth, temperament, vanity, inconfancy, prejudice, custom, in the senses, in love and hatred, in the pagfions, as well as in what affects them.

We find their sources (1) in impatience ; for in order to a found judgment there is requir'd a discernment of relations. Ideas are involved one within another, and it requires time to divide, unfold, and range them in proper order. There is need of patience to dwell long upon the same object, to consider it in all its appearances, and examine it on all fides ; and we are too apt to be impatient. The mind is soon tir'd in its pursuits, if unattended with pleasure, and cares not to employ itself but on ideas whose relations are obvious and easy to be apprehended. It frequently loses even the memory of others, and takes an association of some partial ideas for the ideas themselves; it supposes a perfect where there is but a partial resemblance, passes a judgment on such weak grounds, and too late finds itself in an erros.

2. Another

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