whilst we may see day by day an increased demand for our productions, as each new colony opens another market for our goods, a fresh means of maintaining the thousands of our people, whose subsistence, even at the lowest rate, depends on the supplying luxuries, not necessaries, to increasing multitudes.

A System of Logic; Ratiocinative and Inductice: being a connected View of the Principles of Evidence, and the Methods of Scientific Investigation. By JOHN STUART MILL. 2 vols. 8vo. London: Parker. 1843.

IN our number for October (pp. 392-413,) we promised to follow Mr. Mill, to some considerable extent, into the subject of Induction. This promise we shall now endeavour to fulfil.

Reasoning, or Inference, we then observed, is not confined to Ratiocination, or the process of inferring a proposition from other propositions equally or more general. It also includes the process of inferring a proposition from propositions less general than itself, or the process of Induction. The conclusion in an induction embraces more than is contained in the premisses. In every induction we proceed from truths which we know, to truths which we do not know; from facts certified by observation to facts which we have not observed, and even to facts which are not now capable of being observed-future facts, for example; but which we do not hesitate to believe upon the sole evidence of the induction itself.

"When, from the observation of a number of individual instances, we ascend to a general proposition, or when, by combining a number of general propositions, we conclude from them another proposition still more general, the process, which is substantially the same in both instances, is called Induction."-Vol. i. p. 223.

The nature of Induction, says Mr. Mill, and of the conditions which render it legitimate, is the main question of the science of logic inasmuch as all inference, and consequently all proof and all discovery of truths not self-evident, consist of inductions and their interpretations; so that all our knowledge, which is not intuitive, comes to us exclusively from that source. Hitherto, however, this subject has been comparatively neglected. Although it is the primary question of logic, professed logicians have almost entirely passed it by. Metaphysical writers have noticed some of the generalities of the subject; but in consequence of their not being practically acquainted with the actual inductive processes by which the discoveries of science have been made, they have not accomplished a sufficiently minute analysis of the inductive operation,

so as to furnish a collection of practical rules for its performance. Physical experimentalists have in general confined their attention to the conclusions arrived at by means of induction, without entering into any inquiry as to the nature of the mental process itself, by which their conclusions were obtained. At the same time, the materials for the construction of the Science of Induction exist in great abundance, and only require a master-hand to collect and arrange them. Three eminent writers are honourably named by Mr. Mill, as having made valuable contributions to the creation of a Philosophy of Induction :-Sir John Herschell, in his Discourse on the Study of Natural Philosophy; Mr. Whewell, in his History and Philosophy of the Inductive Sciences; and M. Auguste Comte, in his Cours de Philosophie Positive. Encouraged by the collection and partial elaboration of the materials by these accomplished philosophers, Mr. Mill has attempted, in his own laborious and thoughtful work, to contribute something farther to the accomplishment of this important design.

Induction is the operation of discovering and proving general propositions. The principles and rules of induction, as directed to this end, are the principles and rules of all induction; and the logic of science is equally applicable to all inquiries in which man can engage, and the test of all the conclusions at which he can arrive by

inference.

"A complete logic of the sciences is also a complete logic of practical business and common life. Since there is no case of legitimate inference from experience, in which the conclusion may not legitimately be a general proposition; an analysis of the process by which general truths are arrived at, is virtually an analysis of all induction whatever. Whether we are inquiring into a scientific principle or into an individual fact, and whether we proceed by experiment or by ratiocination, every step in the train of inferences is essentially inductive; and the legitimacy of the induction depends in both cases upon the same conditions."-Vol. i. p. 348.

In studying the nature of induction, we must be careful to distinguish it from certain operations to which the name of induction has been unjustly applied. Such are the so-called forms of induction laid down in the common books of logic.

"In those books, every process which sets out from a less general and terminates in a more general expression,-which admits of being stated in the form, 'This and that A are B, therefore every A is B,'-is called an induction, whether anything be really concluded or not; and the induction is asserted to be not perfect, unless every single individual of the class A is included in the antecedent or premiss: that is, unless what we affirm of the class, has already been ascertained to be true of every individual in it, so that the nominal conclusion is a mere reassertion of the premisses.”– Vol. i. p. 353.

Such an induction as this is no induction at all. It is no inference from facts known to facts unknown, but a mere short-hand registration of facts already known. It is no part of the investigation of truth; though it often bears an important part in the preparation of the materials for that purpose.

That process to which mathematicians give the name of induction, must also be distinguished from induction as defined above: for although the propositions to which it leads are really general, yet there is no inference; the conclusion being a mere summing up of what was asserted in the various propositions from which it was drawn.

"There are nevertheless, in mathematics, some examples of so-called induction, in which the conclusion does bear the appearance of a generalization grounded upon some of the particular cases included in it. A mathematician, when he has calculated a sufficient number of the terms of an algebraical or arithmetical series, so as to have ascertained what is called the law of the series, does not hesitate to fill up any number of the succeeding terms without repeating the calculations. But I apprehend he only does so when it is apparent from à priori considerations (which must be exhibited in the form of demonstration) that the mode of formation of the subsequent terms, each from that which preceded it, must be similar to the formation of the terms which have been already calculated. And when the attempt has been hazarded without the sanction of such general considerations, there are instances upon record in which it has led to false results."-Vol. i. p. 355.

Once more: a mere description of a set of observed phenomena must not be confounded with an induction from them. Mr. Mill considers Mr. Whewell to have fallen into the error of setting up that descriptive operation which enables a number of details to be summed up in a single proposition,-(and which Mr. Whewell has aptly termed "the Colligation of Facts,")—as the type of the inductive process; and of laying down as principles of induction the principles of mere colligation. Mr. Whewell's doctrine, as we have previously shown in our pages, is, that the general proposition which binds together particular facts, and makes them, as it were, one fact, is not the mere sum of those facts, but something more; since a conception of the mind is introduced, which did not exist in the facts themselves. Among many examples, Mr. Whewell adduces the following. The italics are our own :

"When the Greeks, after long observing the motions of the planets, saw that these motions might be rightly considered as produced by the motion of one wheel revolving in the inside of another wheel, these wheels were creations of their minds, added to the facts which they perceived by sense. And even if the wheels were no longer supposed to be material, but were reduced to mere geometrical spheres or circles, they were not the less products of the mind alone, -something additional to the facts observed. The same is the case in all other discoveries. The facts are known, but they are insulated and unconnected, till the discoverer supplies from his own store a principle of connexion."*

That a conception of the mind is introduced, replies Mr. Mill, is indeed most certain; but it by no means follows that the conception

* Philosophy of Inductive Sciences, ii. 213, 214.

is necessarily pre-existent, or constructed by the mind out of its own materials.

"Although the conception itself is not in the facts, but in our mind, it must be a conception of something which is really in the facts, some property which they actually possess, and which they would manifest to our senses, if our senses were able to take cognizance of them."Vol. i. p. 361.

Having thus excluded those mental operations which are sometimes designated by the name of induction, while, at the same time, he admits and asserts their importance, especially of the last, as subsidiary to induction properly so called, Mr. Mill_summarily defines this great mental process as Generalization from Experience. It consists, he observes, in inferring from some individual instances in which a phenomenon occurs, that it occurs in all instances of a certain class. The nature of this class, at the present stage of the inquiry, remains to be determined.

"The universe is so constituted, that whatever is true in any one case, is true in all cases of a certain description. The only difficulty is to find what description."-Vol. i. p. 370.

arc

This universal fact is the basis of all induction. It has been variously stated; as, that "the course of nature is uniform;" that "the universe is governed by general laws;" and the like. Many philosophers regard this fundamental axiom as one which we compelled, by the constitution of our thinking faculty, to assume as true, antecedently to any verification from experience. Mr. Mill, on the contrary, considers it to be an instance of induction, and induction by no means of the most obvious kind.

"Far from being the first induction we make, it is one of the last, or, at all events, one of those which are latest in attaining strict philosophical accuracy. As a general maxim, indeed, it has scarcely entered into the minds of any but philosophers; nor even by them, have its extent and limits been always justly conceived. Yet this principle, though so far from being our earliest induction, must be considered as our warrant for all the others, in this sense, that unless it were true, all other inductions would be fallacious."-Vol. i. p. 372.

The lowest kind of induction, resting upon this basis, is that which Lord Bacon has described, under the name of Inductio per enumerationem simplicem, ubi non reperitur instantia contradictoria. This is the natural induction, if it deserves the name, of uncultivated intellects; and flows from the instinctive tendency of the mind to generalize its experience, provided that experience points all in one direction. In this unscientific process, there is no "interrogation of nature," to use Lord Bacon's expression. The mind rests in a mere passive observation: its ear receives no other sounds from the mighty oracles of Nature, than those which flow spontaneously from the lips of the Ancient Mother. This induction by simple enumeration, is but a feeble instrument for the purposes of scientific investigation; and even for merely popular use, is as fruitful of error as of truth.

"It was, above all, by pointing out the insufficiency of this rude and loose conception of Induction, that Bacon has merited the title so generally awarded to him, of Founder of the Inductive Philosophy. The value of his own contributions to a more philosophical theory of the subject, has certainly been exaggerated. Although (along with some fundamental errors) his writings contain, more or less fully developed, several of the most important principles of the Inductive Method, physical investigation has now far outgrown the Baconian conception of Induction. Moral and political inquiry, indeed, are as yet far behind that conception. The current and approved modes of reasoning on these subjects, are still of the same vicious description against which Bacon protested: the method almost exclusively employed by those professing to treat such matters inductively, is the very inductio per enumerationem simplicem which he condemns; and the experience, which we hear so confidently appealed to by all sects, parties, and interests, is still, in his own emphatic words, mera palpatio.”— Vol. i. p. 378.

To return to our fundamental axiom. Instead of saying that the course of nature is uniform, it would be more correct to say that, the course of each of the separate phenomena, comprehended in the word “nature," is uniform. What is called the uniformity of the course of nature, is not a simple, but a complex fact, compounded of all the separate uniformities of single phenomena. These uniformities are usually designated laws of nature; but this appellation more strictly belongs to those uniformities which are primordial.

"When Kepler expressed the regularity which exists in the observed motions of the heavenly bodies, by the three general propositions called his laws, he, in so doing, pointed out three simple volitions, by which, instead of a much greater number, it appeared that the whole scheme of the heavenly motions, so far as yet observed, might be conceived to have been produced. A similar and still greater step was made, when these laws, which at first did not seem to be included in any more general truths, were discovered to be cases of the three laws of motion, as obtaining among bodies which mutually tend towards one another with a certain force, and have had a certain instantaneous impulse originally impressed upon them. After this great discovery, Kepler's three propositions, though still called laws, would hardly, by any person accustomed to use language with precision, be termed laws of nature:' that phrase would be reserved for the simpler laws into which Newton, as the expression is, resolved them."--Vol. i. p. 385.

Of all truths relating to natural phenomena, the most valuable to us, are those which relate to the order of their succession; and one of our greatest scientific desiderata is to find, if possible, some law of succession which possesses the same degree of certainty and universality as that belonging to the fundamental truths of geometry and arithmetic, the sciences of space and number. Very few of the uniformities observed in the succession of phenomena possess this character. One such there is, however, and happily it is one, as Mr. Mill observes, coextensive with the entire field of successive phenomena, all instances whatever of invariable succession being examples. This law is the Law of Causation.

Abstaining from all inquiry into the nature of efficient causes, as belonging to transcendental philosophy rather than to logic, Mr. Mill