fibres proportionate to the multiplicity of separate touches, whether produced by the exploration of other things or by self-exploration; and that where it results from selfexploration, there also go on the above-described concomitant developments.

We have now only to glance at one or two general corollaries from these interpretations.

§ 345. Besides the establishment of a connexion in thought between each particular muscular series and the particular tactual series, both successive and simultaneous, with which it is associated in act; and besides the implied establishment of a knowledge of the special muscular adjustments required to touch each special part; there must be a still more decided establishment of a connexion between muscular series in general and series of sequent and coexistent positions in general; since this connexion is repeated in every one of the particular experiences. And when we consider the infinite repetition of these experiences, we shall have no difficulty in understanding how their components become so consolidated, that even when the hand is moved in the dark without touching anything, it is impossible to be conscious of the muscular sensations without being conscious of the sequent and coexistent positions-the Time and Space-in which it has moved.

Observe again, that as, by this continuous exploration each point on the skin is put in relation with multitudinous points that lie not in one direction only but in all directions, it follows that when an object of some size is placed on the skin, the impressions from all parts of the area covered being simultaneously presented to consciousness, occupy coexistent positions before consciousness: whence results an idea of the superficial extension of that part of the body. The idea of this extension is really nothing more than a simultaneous presentation of all the impressions proceeding from the various points it includes, which

have previously had their several relative positions measured by means of the series of impressions separating them. Any one who hesitates respecting this conclusion, will, I think, adopt it, on critically considering the perception he has when placing a book against his cheek-on observing that the perception is made up of many elements which he cannot think of all together-on observing that there is always one part of the whole surface touched, of which he is more distinctly conscious than of any other part-and on observing that to become fully conscious of any other part, he has to traverse in thought the intervening parts; that is, he has to think of the relative positions of these parts by vaguely recalling the series of states of consciousness which a motion over the skin from one to the other would involve. It is needless now to dwell on that development of these fundamental ideas which results when the visual experiences are united with the tactual and muscular experiences. Being merely a further complication of the same process, it may readily be traced out by joining with the above explanations, those given when treating of visible extension and space. Here I need only add that, by serving clearly to establish in our minds the identity of subjective and objective motion, sight enables us to dissociate Motion almost entirely from those muscular sensations through which it is primarily known to us; and that by doing this, and by so reducing our idea of Motion to that of coexistent positions in Space occupied in successive positions in Time, it produces the apparently necessary connexion between these three ideas.

§ 346. We conclude, then, that the consciousness of Motion, originally present under the form of a series of muscular sensations, serves by its union with tactual experiences to disclose Time and Space to us; and that, in the act of disclosing them, it becomes clothed with the ideas of them, and ultimately becomes inconceivable without these ideas.

It remains to say that the perception of Motion, as we know it, consists in the establishment in consciousness of a relation of simultaneity between two relations—a relation of coexistent positions in Space, and a relation of sequent positions in Time (with which, however, there necessarily goes the consciousness of a something that occupies these positions successively). And in the act of perception, these jointly-presented relations are severally assimilated to the like relations before known. Thus the perception of great velocity is possible only by simultaneously thinking of two coexistent positions as remote, and two sequent positions as near which words remote and near, imply the classing of the two relations with previously-experienced ones. And similarly with perceptions of the kind of motion, and the lirection of motion.

CHAPTER XVII.

THE PERCEPTION OF RESISTANCE.

347. We may conclude, à priori, that of the various impressions received by consciousness, there must be some most general impression. The building up of oo experiences into a complex structure, implies a fundamental experience on which the structure may rest. By successive decompositions of our knowledge into simpler and simpler components, we must come at last to the simplest—to the ultimate material-to the substratum. What is this substratum? It is the impression of resistance. This is the primordial, the universal, the ever-present constituent of consciousness.

It is primordial in the sense that it is an impression of which the lowest orders of creatures show themselves susceptible, and in the sense that it is the first species of impression received by the highest creatures: it is appreciated by the nerveless tissue of the zoophyte, and is presented in a vague manner even to the nascent consciousness of the unborn child.

It is universal, both as being cognizable (using that word not in the human but in a wider sense) by every creature possessing any sensitiveness, and usually as being cognizable by all parts of the body of each-both as being common to all sensitive organisms, and mostly as being common in greater or less degrees to their entire surfaces.

It is ever present, inasmuch as every creature, or at any rate every terrestrial creature, is subject to it during the whole of its existence. Excluding those lowest animals which make no visible response to external stimuli, and those which float passively suspended in the water, there are none but what have, at every moment of their lives, some impressions of resistance; proceeding either from the surfaces on which they rest, or from the reactions of their members during locomotion, or from both.

Thus, impressions of resistance as being the earliest that are appreciated by the sensitive creation regarded as a progressive whole, as well as by every higher animal in the course of its evolution; and as being more or less appreciated by all parts of the body in the great majority of animals; are necessarily the first materials put together in the genesis of intelligence. And as being the impressions continuously present in one form or other throughout life, they necessarily constitute that thread of consciousness on which all other impressions are strung-form, as it were, the weft of that tissue of thought which we are ever weaving. But leaving general statements, let us go on to consider these truths somewhat in detail.

§ 348. That our perception of Body has for its ultimate elements impressions of resistance, is a conclusion to which all the foregoing analyses point. In the order of thought (and of any other order we can know nothing) resistance is the primary attribute of body; and extension is a secondary attribute. Here is the evidence.

We know extension only through a combination of resistances. We know resistance immediately by itself; for though to a developed intelligence the consciousness of position is given along with the consciousness of resistance, it is clear that were the consciousness of position absent this would not involve the absence of the consciousness of resistance. Again, a thing