As the analytic method of communicating any truth is, properly speaking, nothing more than a copy of the method of its investigation, the more minute delineation of this process is best referred to logic, which treats profeffedly of the nature of those investigations. Little, therefore, needs to be added here to what was faid in the comparison of the two methods, and the cases in which they are each of them best applied. A few obfervations in this place fhall fuffice.

Notwithstanding the analytic method of communicating truth be properly a copy of the method of investigation, it is manifeftly fuperfluous to relate every step of any actual process. As it could not but happen that, in the course of every inquiry, a variety of observations muft have occurred which were foreign to the purpose, and many hypotheses have fuggefted themselves which subsequent obfervations obliged us to reject. These abortive notions, contributing nothing to the illuftration of the fubject, it is most adviseable, in general, to omit; unlefs, in confequence of confiderable ftrefs having been previously laid upon them, it be requifite to show that fuch stress was unreasonable; that particular facts and obfervations, which had been urged in treating upon that fubject, had no relation to it, and that particular hypotheses, advanced and contended for by others, were ill founded. Much more, therefore, may often, with advantage, be introduced into an analytic inquiry, which is made after other unsuccessful inquiries, and particularly when popular prejudices have been adopted upon any subject, than would be neceffary or proper, in a discussion intirely new, and with respect to which there were, confequently, few prejudices to obviate, and few objections to anfwer.

In this latter cafe, that fet of obfervations is the best chofen which leads moft directly to that only hypothefis which we have in view, and intend to establish; and the moft pleafing, as well as the most fatisfactory method of conducting fuch an inquiry is, that which is as near an imitation as poffible of the method of approximation, in feveral of the mathematical fciences. Let the final discovery be opened by degrees, by advancing, in the first place, fuch obfervations as make our hypothefis only probable, or which conclude equally in favour of it and fome others. Let the probability grow ftronger by degrees, by fubfequent obfervations excluding, in their turns, more and more of the remaining hypothefes; and let the experimenta crucis, which abfolutely exclude all others whatever, be referved for the laft.

When writers do not difpofe their arguments in this manner, "they lofe," as Dr. Hartley well obferves, " much of their clear"nefs and force. Sir Ifaac Newton's Optics, Chronology, and "Comment on Daniel," he fays, " abound with inftances to this " purpose; and it is probable that his great abilities and practice "in algebraic investigations led him to it infenfibly."

Since example contributes as much to inftruction as precept, I shall, for the farther illuftration of these rules, fubjoin an account of the method in which fome of our most celebrated and approved writers have conducted their argumentative discourses upon fome important fubjects.

I fhall only premife one general obfervation, which is, that treatises written profeffedly upon the whole of any branch of science, and which are not taken up with the difcuffion of any fingle queftion, are necessarily of a very mixed nature, with respect to their method. For, according to the received divifions of fcience, they muft, generally, confift of parts that are of a nature

very different from one another, and which, therefore, require to be difcuffed in a very different manner. Sometimes a regular demonstration is ufed; in other places the analyfis is preferred,. and the practical parts of the science are explained in the method of didactic narration, intermixed with the reafons (borrowed. from the scientific parts of the fubject) on which the precepts are founded.

MR. LOCKE, propofing, in his excellent Treatise on the Human Understanding, to inquire into the origin, certainty, and extent of human knowledge, together with the grounds and degrees of belief, opinion, and affent; confiders, in the first place, all the properties and diftinctions of ideas, as the elements of all our knowledge, and traces the fources from which, and the channels by which, they are conveyed to our minds. He then confiders in what manner, and with what degrees of accuracy, words are made to reprefent all these varieties of ideas, with what relates to the proper ufe and abufe of words; and, laftly, from thefe preliminaries, as fo many certain facts and data, he draws the conclufions he had in view, concerning the nature and bounds of that knowledge, which refults from the perception of the properties and relations of these ideas, and the imperfection attending the communication of this knowledge by words. All, there fore, that he advances upon the fubject of ideas and words must be confidered as definitions, axioms, or lemmas, to be used in the demonstration of the propofition he lays down in the remaining part of the treatise.

In examining the properties of fome claffes of ideas, he is led into large difquifitions concerning fome particular ideas; as thofe of power, identity, &c. but whether his opinions concerning

thefe

these ideas be just or not, it by no means affects the truth or usefulness of the bulk of his obfervations and conclufions.

His manner of amplification is very diffuse, and his method in the former part, didactic and narrative; relating a series of obfervations on the properties of ideas, with a tacit appeal to every man's consciousness of the truth of what he advances.

In MR. HUTCHESON's Treatife of Moral Philofophy, we are first presented with a narrative delineation of the several powers and principles of human nature, the juftness of which human experience and human actions are fuppofed to avouch. Having delineated the internal frame of man, he defcribes the various uses to which these powers may be applied, and the various pleafures and enjoyments we receive by their means. The nature of each of these species of pleasure he examines separately, in order to determine which of them contributes moft to human happinefs, and thereby conftitutes the chief good of man.

The refult of this analytical inquiry is, that the chief good of man confifts in the gratification of those affections which have the happiness of our fellow-creatures for their object, or are connected with it; which affections are termed virtuous.

Virtue, thus explained, he branches out into its feveral kinds, and particularly fhews the extent of it, as respecting God, mankind, and ourselves. Laftly, he demonftrates, more particularly, the various obligations of virtue, in the principal cafes that may occur in a state of nature, and likewife those which occur in a ftate of civil fociety; the right, and the lawful, in every cafe being determined by the tendency any action hath to promote the good of mankind in general, or of any particular fociety whofe intereft is confiftent with it.

LECTURE X.

Of the METHOD of Mr. Hume's Inquiry into the Principles of Morals, Hartley's Obfervations on Man, Harris's Hermes, that of Sermons, and of Mifcellaneous Writings,

TH

HE plan of the most valuable part of Mr. HUME's inquiry concerning the principles of morals, is nearly the fame with that part of Mr. Hutchefon's Moral Philosophy, which corre sponds to it, and may moft properly be termed analytical. For,, in order to determine the foundation of virtue, he confiders particularly every thing that is acknowledged to gain the esteem of mankind; examining upon what common property it is that their encomiums turn, and in what measure their approbation is be-flowed; and having found that nothing is the object of esteem but what is useful to fociety, and, moreover, that the feveral virtues are claffed in the firft or fecond rank of importance, ac-cording as they are more or lefs effential to the well-being of fociety, he concludes, that public utility is the foundation of alli

virtue..

This ingenious writer greatly excels in his method of conduct-ing argumentative discourses, and, particularly, we fee clearly in his writings the advantage of propofing fingular opinions in the method of analyfis. The greater part of his discourses are fo