fession, tells him,

logick is certainly dry and unentertaining, but stretch all the nerves and sinews of your mind to attain it, for it is of infinite use in setting a keen edge upon the understanding, and be. sides it gives an eagle eye in detecting false reasoning and sophistry. I never knew an able logician who did not acknowledge and feel the utility of it in forensic practice."

We do not consider the rules and classifications of logic as practically to be adopted in the emergencies to which they are systematically applicable; they are too abstracted and too subtle, and the process is too slow and cumbrous. It is as

a discipline of the mind, as teaching it the more readily to detect, and the more briefly and effectually to expose, fallacies in reasoning,—that this head of science is of the most

use.

Mr. Kirwan has shewn judgment and diligence in his selections of what was essential to his subject, from the works of his more approved predecessors. The most considerable of his additions occur in the chapters which treat of proposi tions; in the parts in which Ratiocination, and its essential principles and different effects, are considered; in the chapters in which calculation is applied to probability; and in those which investigate the means that are requisite to obtain truth from living witnesses, and the methods of interpreting written documents.

The detail which is here given of the varieties of proposi tions is justified on the ground that so much use is made of them in legal and theological controversies: but a better reason, perhaps, is that which was assigned on the same occasion by Messieurs de Port-royal, namely the useful exercise for the mind which the subtlety and intricacy of the disquisitions supply.

In treating on the effects of ratiocination, we could have wished that the author had gone farther into the philosophy of the subject, and had familiarized the student with the illustra tions of it which have been given by Dr. Hartley.

Our readers will be able to form a judgment of the style of this performance from the following specimens:

A very important mistake with respect to the use of words has been committed by most writers, previous to the age of the discerning Berkeley, in supposing that general words primarily denoted general abstract ideas. For since it is certain that ideas are transcripts of things perceived by sense, it is evident that since no general thing exists, but all existing things are particular, so ideas must be the transcripts of particular things only thus as all the men now exist ing (or that have ever existed) are particular individuals, and as no such thing can exist as man in general, so all ideas of men must be the ideas of particular men, and not of man in general, unless the idea of

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one

one particular man may be said to represent, as it does in many respects, all men. Thus a line an inch long, may be said to represent a line of any length; for when a geometrician requires you to draw a line, he leaves it to your choice to draw a line of any length you please; or if he requires you to form a triangle, without saying any thing more, he leaves it to your choice to form an equilateral triangle, an isosceles, or a scalenum. Which ever of these you form, it represents all the others in the general properties of a triangle. Thus the proposition, that the three angles of a right-lined triangle, are equal to two right angles, is equally true with respect to any of the abovementioned.'

There is also a circumstance which rendered this subject dark and intricate, first discovered by Dr. Berkeley, which must appear surprising to every one; namely, that words are understood even when they excite no distinct idea or notion whatsover. Thus the words or figures 102 and 108, for instance, are well understood, and the latter known to exceed the former, though we can form no idea or representation of either of these numbers abstracted from the words or figures that denote them; nay, not even if they were applied to particular things. It is then sufficient that we should know that their precise meaning was once definitely understood by us, and may still, if investigated, be clearly assigned and enumerated; nay, the ideas even of sensible things do not arise in our minds, when the words that denote them are heard.'

In the subsequent passage, the author clearly convicts Mr. Hume of a gross inadvertence:

Mr. Hume thinks that chance properly denotes the negation of any cause; but that an event should happen without any cause, appears to me, and to the rest of mankind, perfectly impossible. He grounds this assertion on the observation, that chance leaves the mind perfectly indifferent, either to consider the existence or non existence of the object, regarded as contingent; whereas this indifference evidently arises from the known equality of the causes that lead to dif ferent events, and ignorance of the circumstances leading to the effect of some one of them, which must destroy the apprehended equilibrium. Thus we know that there are on one common die, six sides, on each of which, after projection, it is capable of resting, and of thus presenting a different face; but of the circumstances that determine it to rest on one face rather than on another, we are ignorant, and conse quently we are left in a state of indifference, or rather of indecision. He adds, "that since an entire indifference is essential to chance, no one chance can possibly be superior to another, otherwise than as it is composed of a superior number of chances." It is strange he did not perceive the absurdity of superior number of nothings."

The most novel part of the first volume is that which treats of the application of calculation to probability. Such disquisitions are properly introduced in a treatise of logic; and the doctrine is stated by the author with great clearness, and well elucidated. We are, however, far from thinking that it

has

has enabled him to furnish us with that logical balance, which correctly ascertains the weight of moral proofs. In our opinion, the general rules and conclusions, at which writers on this subject have arrived, are rather indirectly than directly aiding to the exercise of our judgment on moral subjects; they rather furnish analogies and suggest reflections, which extend our views and assist our apprehensions, than admit of any precise application in reference to moral inquiries; and, regarded in this light, we consider them as of very high utility. This part of the present work has been very successfully executed; and, aware of the importance and curious nature of the topic, Mr. K. has taken laudable pains to render it intelligible to persons of ordinary comprehensions and attainments. His manner of treating it may be collected from the ensuing extract:

The known possibility of any event is called a chance; and where there are several known causes equally capable of producing different events, it is inferred that there are as many chances of those events; and when it is known that some or other of those causes have acted, or must necessarily act, those chances have been, in a loose way and improperly, called probabilities by writers on the doctrine of chances.

6

The doctrine of chances is that, which from a given number of events equally possible, (as far as we know,) infers the probability or improbability of each, or of the combinations of each; and also from a certain number of events, or combinations of events, infers their causes. The distinction of casual and empiric probabilities has been already noted.

Thus if we take a common die, and suppose the turning up of each of its six faces equally possible, it is certain that on projecting it, some one or other of these six faces will be turned up for it must lie on some or other of these faces, and then the opposite face will appear, and hence each of these faces may be called the cause of the appearance of the opposite face: but as only one of these faces can shew an ace, the chance of throwing an ace, is only one chance out of six chances, or, and the odds against it are five out of six, or of a certainty.

Hence the general rule is, that if among a certain number of equal possibilities or chances, there are some favourable to a given event, that is, tend to produce it, and some adverse to its production, or productive of a different or contrary event, the probability or improbability of such event, is as the number of the favourable chauces, divided by the sum of all the chances, both favourable and unfavour able; as in the last example, there was only one chance of casting an ace, and five chances of throwing other Numbers. The sum of both was 15, that is 6.

Therefore the sum of all the known chances, favourable and unfavourable, to an event, is equal to the sum of all the possibilities of any event. And as those that are favourable are only a part or fraction of the whole number of possibilities, they are expressed by a

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fraction,

fraction, as in the above example, and for the same reason so may those that are adverse to it. Now the favourable and unfavourable together make up the whole of the chances: therefore if the frac tions expressing each of them be added together, they make up an unit. So in the above examples, added to % = = 1.

6

Again, as in every case it is certain that a given event will either happen or not happen, all the possibilities favourable and unfavourable are comprehended, and consequently certainty is expressed by an unit; therefore the highest probabilities are those that are expressed by fractions, that approach most to an unit, though none can ever reach it, for they would then cease to be probabilities, being con. verted into a certainty, though some approach so near to it, that they are usually taken for it, as the probability that the world will last another year, &c.

As certainty is expressed by 1, so is doubt or an equality of chances by. So if in a covered box there are an equal number of black and white balls well mixed, and through a perforation in the box the hand be introduced, that one or other of these balls will be drawn is certain; and as the possibilities are only 2, the chance of drawing a white ball is, and the chance of drawing a black ball is also; and as those possibilities balance each other, consequently which of them will be drawn is uncertain or doubtful.

Note, the word uncertain is capable of two significations, for we are uncertain when we doubt, and also when we are totally ignorant of any reason, whether of affirming or denying; for instance, whether the number of grains of sand in a box is odd or even.

Hence the probability of an event consists in the apparent superiority of the possibilities, causes, or reasons tending to produce the belief of its existence over those that are adverse to that belief, and consequently it is denoted by a fraction higher than, as , &c.

So the improbabi'i'y of an event consists in the apparent inferiority of the possibilities, causes or reasons for believing its existence, to those that oppose them, and therefore it is denoted by a fraction lower thanas,,, &c., remembering always, that the denominator of the fraction comprehends all the possibilities, &c. favourable and adverse. And consequently, by subtracting the favourable (which are found in the numerator) you have the adverse.

--

In the sequel + denotes more, denotes less, X denotes multiplied, and denotes equal, and two or more letters subjoined denote the multiplication of those numbers they stand for into each other.'

An attentive and patient student will derive the greatest advantage from the author's disquisitions on evidence, and particularly from those on the subject of testimony. He will find comprized within a small compass the substance of bulky

volumes.

In many respects, the scientific author of this work seems well qualified for the task which he has undertaken; a mind free from prejudice, perfect impartiality, a philosophical

turn,

turn, analyizing habits, and a sound judgment, are well known to characterize Mr. Kirwan: but these are not all the requisites in a writer on the present topic. Logic is more connected with metaphysics and language than with physics. We would not be understood to deny, nor in any degree to question, that an intimate acquaintance with the latter is indispensible in him who would do justice to the subject of these volumes but we think that a person, who has been principally conversant with physical science, has not passed through the best discipline for treating successfully of logic. To excell in this department, a writer ought to be familiar with the niceties, of language; not only to know the force of terms, but to be acquainted with their meaning in its nicest shades; to select not merely those terms which are appropriate, but those which are the most happy; and if he be deficient in these respects, he will not only fail in his style, but will err in his science. Those who have dwelt with delight on the pages of the Port-royal logic, and who have duly appreciated the felicity of the terms, the precision and neatness of the language, and the matchless clearness of the statements in that work, will feel convinced that much is wanting to render the present treatise perfect.

ART. XIII. The History and Antiquities of the Church and City of Lichfield containing its ancient and present State, civil and ecclesiastical; collected from various public Records, and other authentic Evidences. By the Rev. Thos. Harwood, F.S.A., late of University College, Oxford. 4to. PP. 574. and 6 Plates. 11. 15s. Boards. Cadell and Davies.

WE

E always encourage and favour works of this nature on. account of their utility, and treat them as privileged undertakings. They fill up the chasms in our topography, are repositories of antient usages and traditions, and record events and transactions which would otherwise be lost to history. Besides rendering this public service, they gratify those who are connected with the respective places of which they treat, and prove very convenient to such persons as become temporary residents in those towns or districts. If compilations of this sort admit not several of the excellencies of authorship, it must be granted that, in order to succeed in them, the writer must possess taste, judgment, industry, and a large portion of that knowlege which constitutes the antiquary.

In his preface, Mr. Harwood states that in the volume before us,

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