sist of an object of some kind. This remains so however far back we may insist on penetrating.]

That is, before the logician can set to work he must have his materials before him, and his materials, unlike those of the psychologist, must always be terms, or the notions corresponding to these terms These presuppose a considerable amount of that analysis and synthesis which has been indicated above. The psychologist may afford to start with simple impressions, but the logician's starting point must always be a stage further on. It must be one in which we stand in possession of ‘objects', distinctly recognized as such.

II. A world of objects having thus been, if one may use the expression, roughly put together with sufficient stability and distinctness for the logician to commence to exercise his art upon it, and to investigate to the utmost its unity, homogeneity and inferribility; we have next to pass in review some of the general characteristics which we must postulate in addition if it is to answer the demands we are entitled to make.

The principal claim of this description which we have to urge is best indicated by the demand that the world must be supposed to be pervaded by the same uniform characteristic of objective certainty, existing without any limit in all directions of space and time. That is, its character is not to be supposed as affected in any way by our attitude towards it. The necessity of insisting upon this characteristic has been fully admitted by many writers in one department of the general science of Inductive Logic,-viz. in Probability,-for a rather notorious fallacy, which is sometimes described as that of 'confounding between probability before and after the event', arises almost entirely from confusion on this head. But the characteristic must be equally insisted upon wherever we are dealing with the facts of the material world. We must recognize absolutely no intrinsic difference between the future and the past, between the near and the remote. There may be greater practical difficulties in the way of ascertaining one or the other, but in themselves the logician must regard them as being no more fundamentally distinguished than are the rails which lie before us and behind us on a railway journey. (Our position on the track at the moment, or the direction in which we are moving, does not alter their character. The future and the past must be regarded

as lying stretched out before our view, certain in themselves,to use a common expression the significance of which will be better understood after we have discussed the nature of Laws of Causation, whether we may have succeeded in determining them or not. The reader who has grown up under the influence of Physical Science will probably grant this so readily (within certain limits) that his only surprise will be that it should be considered necessary formally to state it. The sequel however will, I think, show the desirability of an explicit statement. In particular, the doctrine of Hypothetical propositions, as indeed the nature of the whole process of making suppositions or employing the particle 'if', seems to me to turn in part upon the non-contingent character of the universe in itself.

The question of the infinity, or rather indefiniteness of range, of the world of phenomena, though connected with the considerations just mentioned, stands on a slightly different footing. It involves certain physical generalizations, and stands in need of debate rather than of mere assumption on its own merits and convenience. It shall therefore be reserved for discussion at a later stage. But so much as this can be said at the outset, that, so far as we regard the world as available for logical investigation we can listen to no speculative difficulties which would seek to put a limit upon its range of existence or possession of general uniformity. Laws of Causation, or, more strictly, Uniformities in their widest signification,—are our only guiding clue; and if they came to an end anywhere we could not take a single step in advance. (The conception of absolute beginnings or endings, of acts of creation or of annihilation, is entirely debarred to a secondary or derivative science like ours. The comparatively abstract science of Inference in general stands in this respect on the same sort of footing with each of the concrete sciences whose most general principles it includes. Every one knows the position in which the astronomer and the geologist stand. Haunted as they are with frequent suggestions of absolute beginnings and endings, they know that they cannot explain them or even reason about them. Up to every point at which scientific explanation is possible, they are bound to assume that there is no breach of continuity, but that the next step beyond is connected with the one of the moment by the same sort of links as those by which the latter is connected with the ones

which went before. We contemplate the world of phenomena as if it resembled some vast scroll, unrolled to a certain extent before our eyes, but written upon in the same sort of characters from beginning to end; or rather, since we do not recognize either beginning or end, inscribed with writing which may be traced from the midst indefinitely in both directions. Of the unopened parts we guess at the contents from what we have read of the rest, though even of this opened part we can at present decipher only a fragment. But we feel that it is all, so to say, objectively knowable: that the data for knowledge are there before us: and that absolutely no limit is set to the extent over which the same sort of writing may be traced and therefore deciphered at some future time. In the words of Leibnitz, who seems to me to have insisted upon this doctrine most strongly, and to have appealed to it most consistently,-considering the fragmentary nature of so many of the discussions which he has left behind him,-"Le présent est gros de l'avenir: le futur se pourrait lire dans le passé: l'éloigné est exprimé par le prochain."

III. The next postulate which we have to make differs in one important respect from the preceding. The former were at least true, or at any rate could not at the time be shown to be false. But the one upon which we must now insist is certainly false. I call attention to this fact thus plainly at the outset, because it is well to be frank, and because the assumption involved is intimately connected with the essential character of Material Logic as an applied or hypothetical science; i.e. as one in which we employ general principles which can only be applied in so far as we assume a state of things which in strictness does not exist. We proceed to explain this postulate and to point out the necessity for it.

We have then already taken it for granted that the external world is largely made up of objects which exist only,—that is, exist as unities or nameable things,-as they are aggregated together and retained in the mind. So far is sound enough. But the postulate now insisted on is that these objects shall be the same for all intelligences, viz. for all human intelligences, with which alone we are concerned. By this it is not meant that we must assume that the ultimate and immediate sensible impressions which I and other persons experience under

a similar stimulus, must agree:—this is a matter for Psychology to take account of, and to answer, if it admit of a rational answer; but that the various groups into which I combine the phenomena, in framing objects in the mode already indicated, must correspond with the similar groups of other observers and

reasoners.

The full grounds for the necessity of this assumption will only become apparent at a later stage, when we come to discuss the nature of Definition and of the Connotation of names, but its general importance can be recognized at once. We can scarcely observe or reason by ourselves, and we certainly cannot convey our observations or reasonings to others, without language. But unless language convey the same meaning to all within its range of application it ceases to be a medium of communication. And for this purpose it is essential that we should have the same sets of objects before us to observe and name. Not only is it possible for language to mislead, by our misapplying names to the objects which we have clearly before us, but it may also fail by our simply not having the same objects before us. Take the following illustration. Any one who looks upon a surface of stormy sea will not fail to see it divided into a number of tolerably distinct 'objects', i.e. waves. And any other observer at his side will see it somewhat similarly divided, that is he will perceive the same set of objects. But this agreement of observation depends in great part upon contiguity of position. If one person were on shore, and the other at the end of a long pier, they would not see the same objects. A few monster waves might be identified by both, but the observers would differ as to the limits of these, and as regards the rest they would differ altogether. That is, one and the same mass of materials would be grouped into completely distinct sets of objects. And if we were to conceive the observers trying to communicate their observations by language, the very foundation of all language, viz. common reference of sign to thing signified, would fail them. Still more clearly perhaps is this the case with the clouds. Two observers standing on the same spot would closely agree as to the number shape and relative magnitude of the fleecy clouds in the summer sky. But if they were communicating by telephone, at a few miles distance, each would probably find it impossible even to identify any one of the individual objects

which the other attempted to describe to him. These, of course, are extreme instances, but the requirement which thus fails here is yet necessary as a general logical postulate. We cannot either convey or receive information by propositions, we cannot express our uncertainty by help of a question, unless the words which we employ stand for the same things.

How far, then, is this requirement secured as a matter of fact? We must look first to the present, and then to the past and the future.

(1) So far as regards the present, there can be little doubt that the vast majority of people do see the world very much in the same way at least as regards the principal objects which compose it, and about which we have to communicate. The same individual objects are distinguished by us all; we class them into the same general groups; and we analyze them into the same component attributes. But we must not suppose that this harmony is brought about by any intrinsic necessity. Certain simple natural objects, such as the sun and the moon, will take care of themselves; and it is easily seen, in the case of infants, how soon the same individualization takes place when we are dealing with any object which can readily be moved about amongst its surroundings. But when we proceed from such instances as these, where the mental-construction element is relatively small in comparison with that which is forced upon us by nature, to instances in which this element is relatively very large, we find that some other aid than individual sense and judgment has to be invoked. Such an aid is found in language. The real reason why we have the same world before us is largely furnished by the fact that we are social beings in possession of a common means of communication. Language has a most powerful influence in steadying or averaging our perceptive faculties. It acts upon us both individually and collectively. In regard to each individual it aids, as Locke long ago pointed out, in holding together the constituent elements of the more complex objects, and thus enabling us to see again what we had seen before. And in regard to any particular society as a whole, it plays a large part in compelling each of us to see the world as his fellows see it; for it gives the impress required to convert a near approach of perception into an almost complete identity. Add to this that each of us, being born to