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engagements; instead of leaving us, as she does in these cases of vaunted empty profession, in bitter disappointment and disgust.

With this explanation, however, our author does not seem satisfied. He asks, "In the syllogism last referred to, for example, or in any of those which we previously constructed, is it not evident that the conclusion may, to the person to whom the syllogism is presented, be actually, and bonâ fide, a new truth? Is it not matter of daily experience that truths previously undreamt of, facts which have not been, and cannot be, directly observed, are arrived at by way of general reasoning?" (p. 246.) We have already admitted that "Logical Discoveries" may be arrived at by reasoning;-the conclusion, though implied in the premises, may not have been previously perceived by the person, to whom the syllogism is presented; and, therefore, it may be to him, in one sense, a new truth, though not in the sense for which our author pleads. But does he mean to say, that, in the last syllogism referred to, or in any of those he has constructed, or can construct, there is more in the conclusion than is contained in the premises? Unless he means to assert this, his questions are irrelevant. Certainly we should like to see, drawn out in regular form, a valid argument, in which there is something more in the conclusion than is assumed in the premises. Our author's illustration is this :- "We believe that the Duke of Wellington is mortal. We do not know this by direct observation, since he is not yet dead. If we were asked how, this being the case, we know the duke to be mortal, we should probably answer, Because all men are so. Here, therefore, we arrive at the knowledge of a truth not (as yet) susceptible of observation, by a reasoning which admits of being exhibited in the following syllogism :

All men are mortal :

The Duke of Wellington is a man; therefore,

The Duke of Wellington is mortal.

And since a large portion of our knowledge is thus acquired, Logicians have persisted in representing the syllogism as a process of inference or proof; although none of them has cleared up the difficulty which arises from the inconsistency between

that assertion and the principle, that if there be anything in the conclusion which was not already asserted in the premises, the argument is vicious," (pp. 246, 247.) We are rather at a loss to characterise this quotation,-coming, as it does, from the pen of so distinguished a writer. Is this an example of a "bona fide new truth; "-" truths previously undreamt of,arrived at by the way of general reasoning?" Is this a syllogism in which the conclusion contains more than the premises? If it is not, what bearing has it on the point at issue? True, we thus "arrive at the knowledge of a truth not (as yet) susceptible of observation; but we do so, because the premises involve this truth by implication. If we admit that all men are mortal, and that the duke is a man, we only assert in the conclusion what was assumed in the premises; hence the use of the illative conjunction-therefore the Duke of Wellington is mortal. Thus it is with all Reasoning; it merely unfolds what is already wrapt up in our previous knowledge, but which is often as much hid from us, for all practical purposes, till thus developed, as if it had been absolutely unknown.

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This distinction, however, is rejected as worthless. "It is impossible," he says, "to attach any serious scientific value to such a mere salvo, as the distinction drawn between being involved by implication in the premises, and being directly asserted in them. When Archbishop Whately, for example, says, that the object of reasoning is merely to expand and unfold the assertions wrapt up, as it were, and implied in those with which we set out, and to bring a person to perceive and acknowledge the full force of that which he has admitted,' he does not, I think, meet the real difficulty requiring to be explained—namely, how it happens that a science, like geometry, can be all wrapt up' in a few definitions and axioms. Nor does this defence of the syllogism differ much from what its assailants urge against it as an accusation, when they charge it with being of no use except to those who seek to press the consequences of an admission into which a man has been entrapped without having considered and understood its full force. When you admitted the major premise, you asserted the conclusion; but, says Archbishop Whately, you asserted it by implication merely; this, however, can here only mean that you asserted it unconsciously; that you did not know

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you were asserting it; but, if so, the difficulty revives in this shape-Ought you not to have known? Were you warranted in asserting the general proposition without having satisfied yourself of the truth of everything which it fairly includes ? And if not, what then is the syllogistic art but a contrivance for catching you in a trap, and holding you fast in it?" (pp. 247, 248.) We reply: True, the person ought to have known that what he admits implies the point in question; and it is the special business of Logic to make him see and acknowledge this. Nor is this to be considered a trifling or sinister employment. To remind a man of what he had not thought of is often as practically important as to put him in possession of truths absolutely new. Inattention, indifference, passion, prejudice, and a host of evil influences, may so bias and blind him that he may overlook the import and application of admitted truths most intimately connected with his best interests. He who convinces him of his error, and recalls him to his duty, far from "catching him in a trap," will be his true delivery. Logic may be perverted, no doubt, as every good thing may; but to represent it as "solemn trifling," because it only leads us to make use of the knowledge we already possess, betrays singular forgetfulness. Is not this the important duty of the mathematician, the moralist, the divine? Their chief business is to point out what we have already admitted, and to induce us to act accordingly. So is it, in so far as mere reasoning is concerned, with the Logician.

But we must hasten to give this author's method of extricating the syllogism from all difficulty and disgrace. He proceeds :-"From this difficulty there appears to be but one issue. The proposition that the Duke of Wellington is mortal, is evidently an inference; it is got at as a conclusion from something else; but do we, in reality, conclude it from the proposition, All men are mortal? I answer, No.

"The error committed is, I conceive, that of overlooking the distinction between the two parts of the process of philosophising the inferring part, and the registering part; and ascribing to the latter the functions of the former. The mistake is that of referring a man to his own notes for the origin of his knowledge. If a man is asked a question, and is at the

moment unable to answer it, he may refresh his memory by turning to a memorandum which he carries about with him. But if he were asked, how the fact came to his knowledge, he would scarcely answer, because it was set down in his notebook: unless the book was written, like the Koran, with a quill from the wing of the angel Gabriel.

"Assuming that the proposition, the Duke of Wellington is mortal, is immediately an inference from the proposition, All men are mortal; whence do we derive our knowledge of that general truth? No supernatural aid being supposed, the answer must be, By observation. Now, all which man can observe are individual cases. From these all general truths must be drawn, and into these they may be again resolved: for a general truth is but an aggregate of particular truths; a comprehensive expression, by which an indefinite number of individual facts are affirmed or denied at once. But a general proposition is not merely a compendious form for recording and preserving in the memory a number of particular facts, all of which have been observed. Generalisation is not a process of mere naming, it is also a process of inference. From instances which we have observed, we feel warranted in concluding, that what we found true in those instances, holds in all similar ones, past, present, and future, however numerous they may be. We then, by that valuable contrivance of language which enables us to speak of many as if they were one, record all that we have observed, together with all that we infer from our observations, in one concise expression; and have thus only one proposition, instead of an endless number, to remember or to communicate. The results of many observations and inferences, and instructions for making innumerable inferences in unforeseen cases, are compressed into one short sentence.

"When, therefore, we conclude from the death of John and Thomas, and every other person we ever heard of, in whose case the experiment had been fairly tried, that the Duke of Wellington is mortal like the rest, we may indeed pass through the generalisation, All men are mortal, as an intermediate stage; but it is not in the latter half of the process, the descent from all men to the Duke of Wellington, that the inference resides. The inference is finished when we have asserted that all men

are mortal. What remains to be performed afterwards is merely deciphering our own notes.

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Archbishop Whately has contended, that syllogising or reasoning from generals to particulars, is not, agreeably to the vulgar idea, a peculiar mode of reasoning, but the philosophical analysis of the mode in which all men reason, and must do so if they reason at all. With the deference due to so high an authority, I cannot help thinking that the vulgar notion is, in this case, the more correct. If, from our experience of John, Thomas, &c., who once were living, but are now dead, we are entitled to conclude that all human beings are mortal, we might surely without any logical inconsequence have concluded at once from these instances, that the Duke of Wellington is mortal. The mortality of John, Thomas, and company is, after all, the whole evidence we have for the mortality of the Duke of Wellington. Not one iota is added to the proof by interpolating a general proposition. Since the individual cases are all the evidence we can possess, evidence which no logical form into which we choose to throw it can make greater than it is ;' and since that evidence is either sufficient in itself, or, if insufficient for one purpose, cannot be sufficient for the other; I am unable to see why we should be forbidden to take the shortest cut from these sufficient premises to the conclusion, and constrained to travel the 'high priori road,' by the arbitrary fiat of logicians. I cannot perceive why it should be impossible to journey from one place to another unless we 'march up a hill, and then march down again.' It may be the safest road, and there may be a resting-place at the top of the hill, affording a commanding view of the surrounding country; but for the mere purpose of arriving at our journey's end, our taking that road is perfectly optional; it is a question of time, trouble, and danger," (pp. 248-51.)

The originality of these views, and our great anxiety to give as full a development of them as possible, must be our apology for these lengthened quotations. Still we feel, that unless the author's very able disquisitions be read as a whole, in their connexion, with all their varied illustrations, complete justice can scarcely be awarded him. We, therefore, earnestly recommend a careful study of the volumes themselves. He sums up his discussion of the syllogism as follows :- "From the considera

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