A sound and comprehensive acquaintance with the laws of our mental frame is of incalculable utility in the business of education. It gives to those who conduct it, correct views as to its objects. It shows the vast importance of early impressions, and of early attention to the culture of habits and dispositions. It points out the best means for forming those characteristics of intellect and affection which are essential to happiness and usefulness. In addition to these advantages, it enables us more correctly to appreciate the inestimable value of Christianity, and the strength of the evidences on which it is founded. It leads to the most interesting conclusions respecting the worth of Christian precepts, and the exalted nature of Christian motives. It shows us how Christianity "reconciles human nature to itself," and it shows that the truth of it rests upon the well-known laws of the human mind. It directly helps the cause of religion in general, by rendering more obvious the reasons of the divine dispensation, and by the various displays of goodness and wisdom which our mental phenomena present to us. It tends, beyond all other branches of philosophical investigation, to correct, enlarge, and exalt our conceptions of the attributes and character of the Supreme Being, and to lay a foundation for the most rational and exalted piety.

LOGIC.

LOGIC is the science of Reasoning. Its purpose is to direct the intellectual powers in the investigation of truth, and in the communication of it to others. It searches out the principles on which argumentation is conducted, and furnishes rules to secure the mind from error in its deductions. It instructs us in the right use of terms, and distinguishes their various kinds. It analyzes the structure of arguments, and shows how their truth may be discovered, or their fallacy detected. Lastly, it describes those methods of classification and arrangement which will best enable us to retain and apply the knowledge which we have acquired.

It has been remarked that the system of logic, is one of those few theories which have been begun and perfected by the same individual. The history of its discovery, as far as the main principles of the science are concerned, properly begins and ends with Aristotle.

OF TERMS, AND THE OPERATIONS OF THE MIND.

There are three operations of the mind which are concerned in argument. 1st, Simple Apprehension; 2d, Judgment; 3d, Discourse or Reasoning.-1. Sim

ple Apprehension is the notion or conception of any object in the mind analogous to the perception of the senses. It is either incomplex or complex. Incomplex apprehension is of one object, or of several without any relation being perceived between them, as of a man, horse, cards: complex is of several with such a relation, as of a man on horseback, a pack of cards. 2. Judgment is the comparing together in the mind two of the notions or ideas, whether complex or incomplex, which are the objects of apprehension, and pronouncing that they agree or disagree with each other, or that one of them belongs or does not belong to the other. Judgment is therefore either affirmative or negative. 3. Reasoning or Discourse is the act of proceeding from one judgment to another founded upon it, or the result of it.

Words possess no natural, inherent aptness to denote the particular things to which they are applied, rather than others; but acquire this aptness wholly by convention, or general agreement among mankind. Had the connexion between the name and the thing been established by nature, there could have been but one language in the world. Language affords the signs by which the operations of the mind are expressed and communicated.

An act of apprehension expressed in language, is called a Term: an act of judgment a Proposition: an act of reasoning an Argument or Syllogism-as, for example,

Every dispensation of Providence is beneficial, Afflictions are dispensations of Providence,

Therefore afflictions are beneficial," is a Syllogism, the act of reasoning being indicated by the word

"therefore." It consists of three propositions, each of which necessarily has two terms, as “dispensation of Providence," "beneficial," &c.

A syllogism being thus resolvable into three propositions, and each proposition containing two terms, of these terms, that which is spoken of, is called the Subject; that which is said of it, the Predicate: and these two together are called the terms, or extremes, because, logically, the subject is placed first, and the predicate last; and in the middle, the Copula, which indicates the act of judgment, as by it the predicate is affirmed or denied of the subject. It is evident that a term may consist either of one word or several. Whatever term can be affirmed of several things, must express either their whole essence which is called the Species, or a part of their essence, namely, either the material part, which is called the Genus, or the formal and distinguishing part, which is called in logic, Differentia, in common discourse, characteristic. Genus and Differentia, put together, make up the Species; for instance, " rational" and "animal" constitute "man;" so that in reality the Species contains or implies the Genus.

Generalization is one of the purposes to which the process of abstraction is applied; when we draw off or contemplate separately, any part of an object presented to the mind, disregarding the rest, we are said to abstract that part. Thus a person might, when a rose was before his eyes or mind, make the scent a distinct object of attention, laying aside all thought of the color, form, &c. But if, in contemplating several objects, and finding that they agree in certain points, we

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abstract the circumstances of agreement, disregarding the differences, and give to all and each of these objects a name applied to them in respect of their agreement, that is, a common name, as a rose," we are then said to generalize.

An individual is so called, because it is incapable of logical division, which is a metaphorical expression to signify the distinct or separate enumeration of several things signified by one common name. This process is directly opposed to generalization. Definition is another metaphorical word, which literally signifies "laying down a boundary ;" and is used in logic to signify an expression which explains any term so as to separate it from anything else, as a boundary separates fields.

Terms are either singular or universal. A singular term is the proper name of some individual person, place, or thing, as Napoleon, Boston, &c. Universal terms are names indiscriminately applied to many individual beings by reason of certain properties which they possess in common: as man, city, river, mountain. Universal terms make the greatest part of the words of every language. Their signification is designedly imperfect, comprising only the most common and obvious properties of things. They are abridgments of language, happily contrived to facilitate and expedite the intercourse of society.

OF PROPOSITIONS.

A proposition is a verbal representation of some perception, act, or affection of the mind; it is judg