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Inductive, estimated, as it has always been, by the standard of the Deductive, will appear a monster. It appears on that standard only in the third figure; and then, contrary to the rule of that figure, it has an universal conclusion. (V. Analyt. Pr. i. 22, § 8.) But when we look less partially and more profoundly into the matter, our conclusion will be very different. În the first place, we find that the two syllogisms present so systematic a relation of contrast and similarity, that, the perfection of the one being admitted, we are analogically led to presume the perfection of the other. In the propositions, the order of the terms remains unchanged: but the order of the propositions themselves are reversed; the conclusion of the one syllogism forming the major premise of the other. Of the terms the major is common to both; but the middle term of the one is the minor of the other. In the common minor premise, the terms, though identical, have, with the different nature of the process, changed their relation in thought. In the Inductive, the parts being conceived as constituting the whole, are the determining notion; whereas, in the Deductive, the parts being conceived as contained under the whole, are the determined.-But, in the second place, however apparently dissimilar in figure and proportion may be the two syllogisms on this partial standard, it will be found, if we ascend to a higher, that a common general principle regulates a similar, nay, a one exclusive perfection in each. The perfection of figure in all syllogisms is this—that the middle term should be the determined notion in the proposition, the determining notion in the assumption. This condition is realized in the first figure of the deductive syllogism. There the middle term is the subject (contained, determined notion) in the proposition; and the predicate (containing, determining notion) in the assumption. In like manner, in our Inductive syllogism, the middle term is the subject (contained, determined notion) of the proposition, and the constituent (determining notion) of the assumption. Thus, not only are the Inductive and Deductive syllogisms, in a general sense, reversed processes; the perfect figure of the one is the exact evolution or involution of the perfect figure of the other. The same analogy holds with their imperfections. Taking, for example, what logicians have in general given as the perfected figure, but which is, in fact, an unnatural perversion of the Inductive syllogism, (i. e. its reduction to the first figure, by converting the terms of the minor premise,) we shall find that its reversal into a Deductive syllogism affords, as we should have anticipated, only a kindred imperfection (in the third figure.)
We call this reduction of the Inductive syllogism an unnatural perversion, because in the converted minor premise the constituent parts are perverted into a containing whole, and the containing whole into a subject, contained under its constituent parts.'—Edinburgh Review for April, 1833, art. ix.
NOTE (E.) P. 173.
For the extract from Blackstone's unpublished lectures, given in the text, we are indebted to the North American Review for April, 1831, art. ix. : it was communicated to the writer of that able article by Dr. Buckland's uncle. The observations with which the reviewer introduces it are so interesting, that we are tempted to quote them :
• We were never more forcibly struck with the great
distance at which those benighted times (when Galileo was persecuted] have been left, than when on a visit to a friend at the University of Oxford, in England, in 1827. It was upon the occasion of Dr. Buckland's annual geological lecture on horseback. This very novel mode of explaining the greatgeological features of a country being peculiar to that eminent man, we shall, we hope, amuse our readers, by giving a brief account of it.
‘About the hour of noon, near a hundred noblemen and gentlemen on horseback left the city with the Professor, and following the London road at a very animating pace, halted at some gravel pits in the valley. Here Dr. Buckland, dismounting, and gaining a small eminence, addressed the assembly of equestrians in his agreeable, colloquial manner, on the causes which had accumulated the beds of gravel and oyster-shells on which they were standing; he then went rapidly, but very eloquently, into the consideration of great bodies of water in motion, of the abrasion and ruin of the strata, the accompanying denudation of vallies, and the deposit of the detritus ; illustrating the subject from time to time, by pointing to the inequalities of the surrounding country, showing where the gorges had been left on the retreat of the waters, and how the contemporaneous vallies were bounded by the once continuous strata. Having touched upon every prominent feature of the country around, the Professor re-mounted his horse, and proceeded at a hand gallop over the plain, for the Shotover hills, the cavaliers pressing around him, bridle in hand, that no observation which fell from him might be lost. At the foot of the hills he again stopped at a moist, springy place, and took occasion—in adverting to the atmospheric water received by the porous, superficial soil, being here resisted in its descent, and thrown out by a bed of clay—to explain the origin and nature of springs of a particular character. After visiting the pits of Kimmeridge clay, famous for the Deltoid oyster, this equestrian lecture was most worthily concluded by a very eloquent account of the secondary beds in the vicinity of Oxford, and the Saurian and other organic remains found in them; the whole delivered by the Reverend Professor on horseback, receiving the most profound and grateful attention from every person present. At the conclusion, he uncovered his head, and bowing to his auditors, they dispersed, leaving him with his private friends, who, after some further investigations, returned slowly to the city to finish the day at his hospitable board. It was in the course of that evening, that a venerable clergyman, of whose octogenarian life, more than sixty years had been passed in immediate connexion with the University, in answer to a remark we made, that natural sci