the uniformity of design which is displayed in the economy of sensitive beings; to compare the arts of human life with the instincts of the brutes, and the instincts of the different tribes of brutes with each other; and to remark, amidst the astonishing variety of means which are employed to accomplish the same ends, a certain analogy characterize them all ;-or to observe, in the minds of different individuals of our own species, the workings of the same affections and passions, manifesting, among men of every age and of every country, the kindred features of humanity. It is this which gives the great charm to what we call Nature in epic and dramatic composition, when the poet speaks a language "to which every heart is an echo," and which, amidst the manifold effects of education and fashion, in modifying and disguising the principles of our constitution, reminds all the various classes of readers or of spectators, of the existence of those moral ties which unite them to each other, and to their common parent.* - Nor is it only in the material and moral worlds, when considered as separate and independent systems, that this unity of design is perceptible. They mutually bear to each other numberless relations, which are more particularly remarkable, when we consider both, in their combined tendencies with respect to human happiness and improvement. There is also a more general analogy, which these two grand departments of nature exhibit, in the laws by which their phenomena are regulated, and a consequent analogy between the methods of investigation peculiarly applicable to each. I have already repeatedly taken notice of the erroneous conclusions to which we are liable, when we reason directly from the one to the other; or substitute the fanciful analogies between them, which language occasionally suggests, as a philosophical explanation of the phenomena of either. But it does not follow from this, that there is no analogy between the rules of inquiry, according to which they are to be studied. On the contrary, it is from the principles of inductive philosophizing, which are applicable * Outlines of Moral Philosophy, pp. 198, 199, 3d. Edit. to both in common, that we infer the necessity of resting our conclusions in each, upon its own appropriate phe nomena. I shall only add, to what has been now stated on the head of analogy, that the numberless references and dependencies between the material and the moral worlds, exhibited within the narrow sphere of our observation on this globe, encourage, and even authorize us to conclude, that they both form parts of one and the same plan;-a conclusion congenial to the best and noblest principles of our nature, and which all the discoveries of genuine science unite in confirming. Nothing, indeed, could be more inconsistent with that irresistible disposition which prompts every philosophical inquirer to argue from the known to the unknown, than to suppose that, while all the different bodies which compose the material universe are manifestly related to each other, as parts of a connected whole, the moral events which happen on our planet are quite insulated; and that the rational beings who inhabit it, and for whom we may reasonably presume it was brought into existence, have no relation whatever to other intelligent and moral natures. The presumption unquestionably is, that there is one great moral system, corresponding to the material system: and that the connexions which we at present trace so distinctly among the sensible objects composing the one, are exhibited as so many intimations of some vast scheme, comprehending all the intelligent beings who compose the other. In this argument, as well as in numberless others, which analogy suggests in favor of our future prospects, the evidence is precisely of the same sort with that which first encouraged Newton to extend his physical speculations beyond the limits of the Earth. The sole difference is, that he had an opportunity of verifying the results of his conjectures by an appeal to sensible facts: but this accidental circumstance (although it certainly affords peculiar satisfaction and conviction to the astronomer's mind) does not affect the grounds on which the conjecture was originally formed, and only furnishes an experimental proof of the justness of the principles on which it proceeded. Were it not, however, for the palpable confirmation thus obtained of the Theory of Gravity, it would be difficult to vindicate against the charge of presumption, the mathematical accuracy with which the Newtonians pretend to compute the motions, distances, and magnitudes of worlds, apparently so far removed beyond the examination of our faculties.* The foregoing observations have a close connexion with some reasonings hereafter to be offered in defence of the doctrine of final causes. They also throw additional light on what was remarked in a former chapter concerning the unity of truth:-a most important fact in the theory of the human mind, and a fact which must strike every candid inquirer with increasing evidence, in proportion to the progress which he makes in the interpretation of Nature. Hence the effect of philosophical habits in animating the curiosity, and in guiding the inventive powers; and hence the growing confidence which they inspire in the ever-consistent and harmonious conclusions of inductive science. It is chiefly (as Bacon has observed) from partial and desultory researches that scepticism arises; not only as such researches suggest doubts which a more enlarged acquaintance with "I know no author," says Dr. Reid, "who has made a more just and a more happy use of analogical reasoning, than Bishop Butler, in his Analogy of Religion, Natural and Revealed, to the Constitution and Course of Nature. In that excellent work, the author does not ground any of the truths of religion upon Analogy, as their proper evidence. He only makes use of Analogy to answer objections against them. When objections are made against the truths of religion, which may be made with equal strength against what we know to be true in the course of nature, such objections can have no weight."-Essays on the Intell. Powers, p. 54. To the same purpose it is observed by Dr. Campbell, that "analogical evidence is generally more successful in silencing objections than in evincing truth. Though it rarely refutes, it frequently repels refutation; like those weapons which, though they cannot kill the enemy, will ward his blows." Phil. of Rhet. Vol. I. p. 145. This estimate of the force of analogical reaso troversy, is discriminating and judicious. The it to the best advantage is, undoubtedly, in r But after the foregoing observations, I may whether both of these ingenious writers have ance of analogy as a medium of proof, and a knowledge, at the same time, that between the of this species of evidence, there is an essent fute an objection, it may often furnish an argum vincing when employed as a medium of proof probable conjecture, invi : ces, however, the pro rise so high, as to certainty. the universe would dispel, but as they withdraw the attention from those comprehensive views which combine into a symmetrical fabric-all whose parts mutually lend to each other support and stability-the most remote, and seemingly the most unconnected discoveries. "Etenim symmetria scientia, singulis scilicet partibus se invicem sustinentibus, est, et esse debet, yera atque expedita ratio refellendi objectiones minorum gentium: Contra, si singula axiomata, tanquam baculos fascis seorsim extrahas, facile erit ea infirmare, et pro libito, aut flectere, aut frangere. Num non in aula spatiosa consultius foret, unum accendere cereum, aut lychnuchum suspendere, variis luminibus instructum, quo omnia simul perlustrentur, quam in singulos angulos quaquaversus exiguam circumferre lucernam ?" * II. Use and Abuse of Hypotheses in Philosophical Inquiries.-Difference between Gratuitous Hypotheses, and those which are suppported by Presumptions suggested by Analogy.-Indirect Evidence which a Hypothesis may derive from its agreement with the Phenomena.-Cautions against extending some of these Conclusions to the Philosophy of the Human Mind. As some of the reasonings in the former part of this Section may, at first sight, appear more favorable to the use of Hypotheses than is consistent with the severe rules of the Inductive Logic, it may not be superfluous to guard against any such misapprehensions of my meaning, by subjoining a few miscellaneous remarks and illustrations. The indiscriminate zeal against hypotheses, so generally avowed at present by the professed followers of Bacon has been much encouraged by the strong and decided terms in which, on various occasions, they are reprobated by Newton. But the language of this great man, when he happens to touch upon logical questions, must non fingo. Quicquid enim ex phenomenis non deducitur hypotheypotheses, seu metaphysicæ, seu physicæ, seu qualitatum occule, in philosophiâ experimentali locum non habent." See the e end of the Principia. not always be too literally interpreted. It must be qualified and limited, so as to accord with the exemplifications which he himself has given of his general rules. Of the truth of this remark, the passages now alluded to afford a satisfactory proof; for, while they are expressed in the most unconditional and absolute terms, so many exceptions to them occur in his own writings, as to authorize the conclusion, that he expected his readers would of themselves be able to supply the obvious and necessary comments. It is probable that, in these passages, he had more particularly in his eye the Vortices of Des Cartes. "The votaries of hypotheses," says Dr. Reid, "have often been challenged to show one useful discovery in the works of nature that was ever made in that way. In reply to this challenge, it is sufficient, on the present occasion, to mention the theory of Gravitation, and the Copernican system.† Of the former we have the testimony of Dr. Pemberton, that it took its first rise from a conjecture or hypothesis suggested by analogy; nor, indeed, could it be considered in any other light, till that period in Newton's life, when, by a calculation founded on the accurate measurement of the earth by Picard, he evinced the coincidence between the law which regulates the fall of heavy bodies, and the power which retains the Moon in her orbit. The Copernican system, however, furnishes a case still stronger, and still more directly applicable to our purpose; inasmuch as the only evidence which the author was able to offer in its favor, was the advantage which it possessed over every other hypothesis, in explaining, with simplicity and beauty, all the phenomena of the heavens. In the mind of Copernicus, therefore, this system was nothing more than a hypothesis ;-but it was a hesis conformable to Essays on the Intellectual Powers of Ma the same volume, the following assertion occu been made concerning the inward structure of by conjecture. The same thing may be said, works of God, wherein any real discovery has always been made by patient observation, by ac drawn by strict reason observations an have always tended ingenious men ha |