It may be the logical connexion between a general and a particular proposition; as when we say, All ambitious men are miserable; therefore, Julius Cæsar was miserable: the implied connexion being, "Julius Cæsar was ambitious; "it may be the connexion between a particular and a particular; as, Julius Cæsar was ambitious; therefore, He was miserable: the implied connexion being, "All ambitious men are miserable."

It often happens, however, that there is an apparent connexion between certain premises and a conclusion, while the argument is altogether unsound. When these seeming arguments are adorned with the flowers of Rhetoric, and advanced with all the confidence of an oracle, even the cautious and intelligent are apt to be thrown off their guard; then bold assertion, and mere declamation, will assume the semblance and prerogatives of conclusive reasoning. Moreover, when a person suspects or believes that there is some fallacy lurking in an argument, whether clearly and briefly stated, or enveloped in oratorical verbiage, he will often be at a loss to detect and expose it, if he be not acquainted with the principles and laws of sound argumentation.

Take, for example, the following fallacious argument :—

Every virtuous youth is attentive to his studies:
This young man is attentive to his studies;

therefore,

He is a virtuous youth.

In the heat of debate, such an argument might be passed off as valid, more especially if the conclusion were such as we believed or wished to be true. And some might not be able to detect and expose the fallacy, even when thus distinctly stated, and their attention particularly directed to it as being unsound. Yet this argument, in so far as the reasoning is concerned, exactly corresponds with the following:

Every Elephant breathes :

An Eagle breathes; therefore,
An Eagle is an Elephant.

Now, though natural sagacity may enable a person thus to expose a fallacy, by bringing forward another precisely similar,

the conclusion of which is manifestly absurd; and though, on many accounts, it may often be needful, and proper, and highly useful, to act in this way; still, it is much more convenient and satisfactory to have a universal test that we can apply to these seeming arguments, by means of which their fallaciousness may be at once rendered evident. This test Logic provides. By means of the general Maxim, formerly stated, to which all conclusive reasoning is conformed, we are enabled to discover where a fallacy lurks, and to strip it of its vain pretensions. Let the argument be expressed in the form of a regular syllogism. If it be valid, the above Maxim will apply to it; or, without changing its meaning, it can be, by logical rules, reduced to such a form as that it will apply; and then the conclusiveness of the reasoning is evident from the mere form of the expression. To this form, however, a fallacious argument cannot be reduced. When brought as near to it as possible, and when mere symbols are substituted for terms that are fitted or intended to deceive, the unsoundness of the argument is made evident by its not conforming to the universal law of all conclusive reasoning.

For instance, take the example given above:—

Every virtuous youth is attentive to his studies:
This young man is attentive to his studies;
therefore,

He is a virtuous youth.

The parallel example to this, was

Every Elephant breathes:

An Eagle breathes; therefore,

An Eagle is an Elephant.

Each of these, if stated in symbols, will stand thus : "A is B: Cis B; therefore, C is A." Now, the general Rule, that applies to all correct reasoning, is: "whatever is affirmed or denied of a whole class, may be affirmed or denied of everything comprehended under that class." In the above example, "B" is affirmed universally of the class "A;" it may therefore be affirmed of everything included in "A." But, in the next premise, there is no reference made to "A;" "B" is merely affirmed, a second time, of another class, "C," that has

no connexion with "A." No inference, therefore, can be drawn. It is evident that whatever is truly affirmed of a whole class may be affirmed of everything which that class contains; but, it by no means follows, because the same thing may be affirmed of another class, totally different and distinct, that therefore these two classes must be one in every respect. We have here merely two propositions, no way connected together, but repeating the same affirmation respecting two different subjects. From this, evidently, nothing can be inferred.

Take, as another example of sophistical reasoning, the following:

Every proud man is unhappy:

This person is not a proud man; therefore,
He is not unhappy.

This argument is precisely similar to the following:-
Every dog is an animal:

A fox is not a dog; therefore,

A fox is not an animal.

Or thus: "Every A is B: C is not A; therefore, C is not B." Here, "B" is affirmed of the whole of "A;" it might therefore, according to the above rule, be affirmed of everything included in "A;" but in the second proposition, nothing is said to be included in "A," but "C" is merely excluded from the class which "A" represents. There is, therefore, no argument here; since what is truly affirmed of a whole class may be true not only of all included in that class, but also of many other classes beside. Whether, in such apparent arguments, the conclusion be a truth or a falsehood, it is not warranted by the premises, and therefore such arguments are denominated Fallacies.

From these various examples it will be seen what Logic professes to accomplish. Its object is to aid us in constructing and testing valid arguments, and in detecting and exposing such as are fallacious. For this purpose, its chief business is to explain, illustrate, and apply the above-mentioned Universal Principle of all correct Reasoning, as evolving the logical connexion between premises and the conclusions legitimately drawn from them. In order to do this, clearly and accurately, various

logical instruments are necessary; technical language must be employed; divisions and distinctions must be made; and general rules must be laid down; that thus our progress may become more speedy and safe. These will be developed as we proceed. Be it remembered, however, for our encouragement, that these necessary aids in the study of Reasoning are not more numerous or perplexing than are found needful and useful in other branches of study. The technical terms and rules of Grammar, or Arithmetic, or Chemistry, are not at all shorter, or more easily understood, remembered, and applied, than those which the Logician finds it necessary to employ. Let but these be distinctly understood at the outset; let them be firmly fixed in the memory; let skill and readiness be obtained, in their exact application, by practice and perseverance, and they cannot fail of being extensively useful, both in guiding us aright, and guarding us from imposition, in argumentation.

It has been disputed, both in ancient and modern times, whether Logic is an Art or a Science. Some have maintained that it is a Science; others that it is merely an Art ;—some, that it is properly speaking neither; others, that it is both. With this last opinion we coincide. While investigating the theory of reasoning, and instituting an analysis of the principles on which it is conducted, Logic is strictly a Science. while furnishing practical rules to guard the mind from error in its deductions, it is properly an Art. To understand Logic in so far as it is a Science, and in so far as it is an Art, is to comprehend at once its nature, province, and use.

Logic, as a Science, ascertains and exhibits the connexion that must subsist between the propositions of a legitimate argument. It points out the principle on which one proposition is inferred from other propositions, and why, with the given premises, the conclusion drawn is irresistible. Logic, as a Science, has to do with the law that obtains in every act of reasoning, whatever the subject-matter may be, and which law, we have seen, is universally the same. As a Science, it deals with Reasoning itself; as an Art, it lays down rules to enable us to detect the various errors that vitiate the legitimacy of our conclusions. As a Science, it arises out of principles that are self-evident; as an Art, it determines the characteristics of terms and propositions, and thus regulates

the vehicle of reasoning-language-in the various logical forms which it assumes in argumentation. As a Science, it could not practically benefit us in reasoning without these rules; as an Art, it could not satisfy our demands for a theoretical explanation, without its clear dependence on fundamental and self-evident principles. As a Science and an Art, -a practical Science-a scientific Art,-it meets both. It communicates knowledge not only that we may know, but that we may reduce it to practice. It thus commends itself to our intelligence as an instrument of great power for aiding us in conducting the reasoning process ourselves, and for testing it when employed by others-whether for the satisfaction of our own minds, or for the accurate and effective application of our reasoning to the minds of others.

Having thus endeavoured to ascertain the nature and object of Logic, and to define and fix its appropriate limits, we shall now take a rapid sketch of its history, and attempt to remove the prejudices and errors that abound respecting it.

The earliest writer on Logic was Zeno the Eleatic. His work on this subject was divided into three parts. The first treated of consequences; the second, of colloquial argumentation; and the third contained a method of wrangling whereby the disputant might entangle his opponent by sophistical reasoning. Hence arose the Sophists, who were plentifully furnished with the weapons which this art of wrangling supplied, and who discussed with the greatest eagerness the most abstruse or the most trifling topics. It is probable the Greeks considered this an ingenious recreation, and had recourse to it merely for amusement, or for the cultivation of their intellectual powers;-though it might be indulged in too much, and was sometimes prostituted to unworthy purposes. With this art, however, Logic has no concern― but to detect and expose its intricate absurdities. Yet the Sophists retained possession of the philosophic schools from the 35th to the 90th Olympiad.

It is only the second part of Zeno's work that properly belongs to Logic. The interrogatory method of disputation, which he introduced, is founded on strictly logical principles. It was this mode of reasoning that Socrates adopted, wh