stantial Method of Discovery.

The advances which

have, during the last three centuries, been made in the physical sciences;-in Astronomy, in Physics, in Chemistry, in Natural History, in Physiology; these are allowed by all to be real, to be great, to be striking: may it not be, then, that these steps of progress have in them something alike?-that in each advancing movement there is some common process, some common principle? that the organ by which discoveries have been made has had something uniform in its structure and working? If this be so, and if we can, by attending to the past history of science, discover something of this common element and common process in all discoveries, we shall have a Philosophy of Science, such as our times may naturally hope for :-we shall have the New Organ of Bacon, renovated according to our advanced intellectual position and office.

It was with the view to such a continuation and extension of Bacon's design, that I undertook that survey of the History of Science which I have given in another work; and that analysis of the advance of each science which the present work contains. Of the doctrines promulgated by Bacon, none has more completely remained with us, as a stable and valuable truth, than his declaration that true knowledge is to be obtained from Facts by Induction: and in order to denote that I start at once from the point to which Bacon thus led us, I have, both in the History and in the Philosophy, termed the sciences with which I have to do, the Inductive Sciences. By treating of the Physical Sciences only, while I speak of the Inductive Sciences in the description of

my design, I do not, (as I have already elsewhere said*) intend to deny the character of Inductive Sciences to many other branches of knowledge, as for instance, Ethnology, Glossology, Political Economy, and Psychology. But I think it will be allowed that by taking, as I have done, the Physical Sciences alone, in which the truths established are universally assented to, and regarded with comparative calmness, we are better able to discuss the formal conditions and general processes of scientific discovery, than we could do if we entangled ourselves among subjects where the interest is keener and the truth more controverted. Perhaps a more exact description of the present work would be, The Philosophy of the Inductive Sciences, founded upon the History of the principal Physical Sciences.

I am well aware how much additional interest and attractiveness are given to speculations concerning the progress of human knowledge, when we include in them, as examples of such knowledge, views on subjects of politics, morals, beauty in art and literature, and the like. Prominent instances of the effect of this mode of treating such subjects have recently appeared. But I still think that the real value and import of Inductive Philosophy, even in its application to such subjects, are best brought into view by making the progress of political, and moral and callesthetical† truth a subject of consideration apart from physical science.

It can hardly happen that a work which treats of Methods of Scientific Discovery shall not seem to fail in

* Hist. Ind. Sci. Second Edition. Note to the Introduction. + Sec Vol. II. On the Language of Science, Aphorism, XVII.

the positive results which it offers. For an Art of Discovery is not possible. At each step of the progress of science, are needed invention, sagacity, genius;-elements which no Art can give. We may hope in vain, as Bacon hoped, for an organ which shall enable all men to construct scientific truths, as a pair of compasses enables all men to construct exact circles. The practical results of the Philosophy of Science must, we are persuaded, be rather classification and analysis than precept and method. I think however that the methods of discovery which I have to recommend, though gathered from a wider survey of scientific history, as to subject and as to time, than, (so far as I am aware,) has been elsewhere attempted, are quite as definite and practical as any others which have been proposed; with the great additional advantage of being the methods by which all great discoveries in physical science really have been made. This may be said, for instance, of the Method of Gradation, and the Method of Natural Classification, spoken of Book XIII. Chap. VIII.; and in a narrower sense, of the Method of Curves, the Method of Means, the Method of Least Squares, and the Method of Residues, spoken of in Chap. VII. of the same Book. Also the Remarks on the Use of Hypotheses and on the Tests of Hypotheses (Book XI. Chap. v.) point out features which mark the usual course of discovery.

But undoubtedly one of the principal lessons which results from the views here given is that different sciences may be expected to advance by different modes of procedure, according to their present condition; and Nor. Org. Lib. 1. Aph. 61.

that, in many of these sciences, an Induction performed by any of the methods just referred to, is not the step which we may expect to see next made. Several of the sciences may not be in a condition which fits them for such a Colligation of Facts, (to use the phraseology to which the succeeding analysis has led me. See B. XI. C. 1). The Facts may, at the present time, require to be more fully observed, or the Idea by which they are to be colligated may require to be more fully unfolded.

But in this point also, our speculations are far from being barren of practical results. The Philosophy of each Science, as given in the present work, affords us means of discerning whether that which is needed for the further progress of the Science has its place in the Observations, or in the Ideas, or in the union of the two. If Observations be wanted, the Methods of Observation given in Book XIII. Chap. II. may be referred to; if those who are to make the next discoveries need, for that purpose, a developement of their Ideas, the modes. in which such a developement has usually taken place are treated of in Chapters III. and IV. of that Book.

is

Perhaps one of the most prominent points of this work is the attempt to show the place which discussions concerning Ideas have had in the progress of science. The metaphysical aspect of each of the physical sciences very far from being, as some have tried to teach, an aspect which it passes through previously to the most decided progress of the science. On the contrary, the metaphysical is a necessary part of the inductive movement. This, which is evidently so by the nature of the

case, is proved by a copious collection of historical evidences in the first ten Books of the present work. Those Books contain an account of the principal philosophical controversies which have taken place in all the physical sciences, from Mathematics to Physiology; and these controversies, which must be called metaphysical if anything be so called, have been conducted by the greatest discoverers in each science, and have been an essential part of the discoveries made. Physical discoverers have differed from barren speculators, not by having no metaphysics in their heads, but by having good metaphysics while their adversaries had bad; and by binding their metaphysics to their physics, instead of keeping the two asunder. I trust that the ten Books of which I have spoken are of some value, even as a series of analyses of a number of remarkable controversies; but I cannot conceive how any one, after reading these Books, can fail to see that there is in progressive science a metaphysical as well as a physical element ;-ideas, as well as facts,thoughts, as well as things:-in short, that the Fundamental Antithesis, for which I contend, is there most abundantly and strikingly exemplified.

On the subject of this doctrine of a Fundamental Analysis, which our knowledge always involves, I will venture here to add a remark, which looks beyond the domain of the physical sciences. This doctrine is suited to throw light upon Moral and Political Philosophy, no less than upon Physical. In Morality, in Legislation, in National Polity, we have still to do with the opposition and combination of two Elements-of Facts and Ideas; of History, and an Ideal Standard of Action; of actual