does seem to me to be a difference between the above two examples,—a difference of meaning, that is, lying below any difference of wording;-for it is not the same thing to think of 'some men' and to qualify these as 'mortal', as to think of 'some mortals' and to qualify these as 'men' or 'human'. On the other hand, when we are dealing with the other proposition as we actually regard it in the mind, we see that what we are really doing is to call up a certain person, and to assign him two names, and the order in which these two names is imposed is a mere matter of language.

CHAPTER II.

THE FOUNDATIONS OF LOGIC; MORE PARTICULARLY IN THOSE RESPECTS REQUIRED FOR INFERENCE.

(I) SEQUENCES.

THE discussion in the preceding chapter was directed towards the task of what might be described as getting the world ready for the logician to set to work upon it; or rather for getting it ready for that whole group of processes which constitute Science and rational practice, and of which the procedure of the logician is but a part. The position we had reached, so far as external requirements were concerned, was that of an objective world capable of being imbued with order, but not yet regarded as orderly. We had, in fact, got as far as Chaos. The little fragments of consciousness with which the psychologist might be supposed to start were assumed to have been projected outside us, and built up into a multitude of distinct objects possessing attributes which accompany or succeed each other Not a word however had been said about any order amongst these objects. An external world had been constituted, but for anything we had yet seen it might still be a chaos rather than

a cosmos.

What we now propose to do is to take the next step of imbuing this chaos with order. That is, we are to consider certain narrower and more special assumptions which lie at the foundations of Logic in particular. Owing to their close connection with the subject-matter of this science, we shall have to be more minute in explaining and justifying them than was demanded in the case of such extremely general assumptions as those indicated in the preceding chapter.

Bearing in mind then the general scope of Inductive Logic, what we have to do is to aim at explaining and systematizing

the facts of the world throughout their widest possible extent. But as the overwhelmingly larger proportion of these facts is beyond the range of our immediate observation, this implies the discovery of some kind of order, arrangement, or relation among the facts,-I purposely use various and vague expressions at the outset,-for, without this, we may take it for granted that we could not advance many steps on our path. Whatever else Induction may be, it involves a passage from what has been observed to what has not been observed.

What characteristics then ought we to demand in Nature in order to enable us to effect this step? That the principle which is to justify us must be a very broad one,-in fact one of universal application, if all nature is to be regarded as amenable to inference, seems obvious. Moreover such a principle must be an objective one; that is, it must express some regularity amongst the events and phenomena themselves, for it is these primarily, and not our own thoughts, whose arrangement we want to ascertain.

There will, I presume, be a tolerably general agreement in the answer given, viz. that what we are in search of is the doctrine of Causation, in some sense or other. But when we come to put a precise interpretation upon that term of so many significations, we find it no easy task to choose amongst the many which are offered to us. Is what we want the Law of Cause and Effect, in the sense of regular antecedent and consequent, as Mill in common with the majority of the Scotch school would maintain? Is it a small selection of wide physical generalizations,-objective in their application, but derived from subjective necessities, and therefore capable of à priori proof,such as the Persistence of Force, the ultimate Rythmic tendency of all motion, and so on, as Mr Herbert Spencer holds ? Is it one single principle alike for Deductive or Formal and for Inductive or Material Reasoning, such as what Jevons advanced under the title of the Substitution of Similars? Or is it lastly a mere congeries of subordinate physical generalizations, each to be derived from its own special branch of science, but incapable of reduction to unity, and so resulting in no one single system of Inductive Logic, as Hamilton and Mansel maintain?

As I cannot altogether agree with any one of these conflicting views, though each of them contains a certain amount of truth,

the most orderly plan seems to be to commence with a short historic sketch of the doctrine of Causation, in so far as Logic is concerned. By 'historic' here is rather meant 'evolutionary'. I do not for a moment presume to contemplate writing a history of so ancient and varied a conception as that of Cause; nor is it suggested that the analysis which is here given follows accurately the order in which the successive views have been predominantly held. We are confining ourselves entirely to the logical applications of the doctrines in question. It is therefore proposed to do no more than show how some of the various formulæ, of which a selection is given above, have grown by a natural evolution, through the promptings of common sense and the criticisms of the logicians and physicists, in their combined efforts to secure a good foundation for our Inductive inferences.

Any logical account of the treatment of Causation is bound in decency to begin with the Aristotelian view of that relation. For many centuries almost every work on Logic contained substantially the same doctrine, viz. that there are four kinds of Cause, the Efficient, the Material, the Formal and the Final. This account was derived, as need not be said, from the great Authority himself, or rather directly derived from his latin commentator and interpreter, Boethius; but for our present purpose it will be best not to go further back than is necessary in order to exhibit the doctrine as it was commonly held just before it began to be influenced by the rise of accurate physical investigation. The current view for the time being is what we want, and for this purpose the version given by such a widely. circulated handbook as that of Burgersdyck will best answer our purpose. His brief description of the four recognized kinds of Cause is given in the following terms:Quidquid fit ab alio fit: nihil fit a seipso Nulla res finita potest aliquid ex nihilo producere: ergo datur materia ex qua res fiunt, et forma quæ in materiam introducitur cum res aliquæ generantur Denique nihil agit temere

(Causa Efficiens.)

(Causa Materialis.) (Causa Formalis.)

(Causa Finalis.)

This account is still repeated here and there in modern works or modern reprints. Some of it falls in readily enough with familiar modes of thought; some of it has been introduced

there through the agency and influence of the old logicians. But most of the distinctions which it involves are obstinately hostile to the bent of all current thought, whether popular or scientific.

For instance, the distinction between Form and Matter, clear and admissible as it is in certain applications, and so long as we do not wander far from the original physical signification along a metaphorical track, gives rise to endless subtleties when we attempt to generalize its use. We understand exactly what is meant by 'form' in its geometrical application, e. g. the form of a cube in contradistinction to the matter of which it may be constructed. We may also fairly enough speak of the form of a proposition (e.g. the affirmative), or of a reasoning (e.g. the hypothetical), apart from the subject-matter with which they deal; and it is on this ground that we are justified in separating off, and treating apart, what is commonly called Formal Logic. I could even, by a stretch, admit the legitimacy of speaking of the 'form' of the causal relation in general, meaning by this only the characteristics which were considered essential to that relation, say invariability of sequence or whatever else it might be. But given any particular example of Causation, say the melting of wax by fire, to determine exactly what is here meant by the form and the matter respectively seems a rather hopeless piece of subtlety. It is only necessary to notice the straits into which a few conservative logicians have been reduced in their attempts to retain and apply the old distinctions in this particular example, in order to be convinced of their futility for any modern requirement.

The Efficient Cause has shown much greater vitality, being earnestly supported by writers no further removed from our day than Reid and Stewart, and indeed by many even at the present time. Brown, one of the best known Scotch opponents of the doctrine, evidently regarded himself as a bold innovator in maintaining that we have no idea of anything in the way of efficiency beyond mere regularity of sequence. The doctrine that there is some element which may be called 'efficiency' has, it must be admitted, a strong foothold in popular belief; for the natural mind rebels against the view that such active agency as we see around us implies nothing more than mere regularity. But such a doctrine seems none the less inadmis