facts is thus not only seen to be arbitrary and subjective, but in the highest degree improbable as well. The departures from Weber's law in regions where it does not obtain, he explains by the compounding with it of other unknown laws which mask its effects. As if any law could not be found in any set of phenomena, provided one have the wit to invent enough other coexisting laws to overlap and neutralize it! The whole outcome of the discussion, so far as Fechner's theories are concerned, is indeed nil. Weber's law alone remains true as an empirical generalization of fair extent: What we add to a large stimulus we notice less than what we add to a small one, unless it happen relatively to the stimulus to be as great. Weber's law is probably purely physiological. One can express this state of things otherwise by saying that the whole of the stimulus does not seem to be effective in giving us the perception of more,' and the simplest interpretation of such a state of things would be physical. The loss of effect would take place in the nervous system. If our feelings resulted from a condition of the nervemolecules which it grew ever more difficult for the stimulus to increase, our feelings would naturally grow at a slower rate than the stimulus itself. An ever larger part of the latter's work would go to overcoming the resistances, and an ever smaller part to the realization of the feeling-bringing state. Weber's law would thus be a sort of law of friction in the neural machine.* Just how these inner resistances and frictions are to be conceived is a speculative question. Delboeuf has formulated them as fatigue; Bernstein and Ward, as irradiations. The latest, and probably the most real,' hypothesis is that of Ebbinghaus, who supposes that the intensity of sensation depends on the number of neural molecules which are disintegrated in the unit of time. There are only a certain number at any time which are capable of disintegrating; and whilst most of these are in an average condition of instability, When the pans of * Elsas: Ueber die Psychophysik (1886), p. 41. a balance are already loaded, but in equilibrium, it takes a proportionally larger weight added to one of them to incline the beam. some are almost stable and some already near to decomposition. The smallest stimuli affect these latter molecules only; and as they are but few, the sensational effect from adding a given quantity of stimulus at first is relatively small. Medium stimuli affect the majority o" the molecules, but affect fewer and fewer in proportion as they have already diminished their number. The latest additions to the stimuli find all the medium molecules already disintegrated, and only affect the small relatively indecomposable remainder, thus giving rise to increments of feeling which are correspondingly small. (Pflüger's Archiv. 45, 113.) It is surely in some such way as this that Weber's law is to be interpreted, if it ever is. The Fechnerian Maasformel and the conception of it as an ultimate psychophysic law' will remain an 'idol of the den,' if ever there was one. Fechner himself indeed was a German Gelehrter of the ideal type, at once simple and shrewd, a mystic and an experimentalist, homely and daring, and as loyal to facts as to his theories. But it would be terrible if even such a dear old man as this could saddle our Science forever with his patient whimsies, and, in a world so full of more nutritious objects of attention, compel all future students to plough through the difficulties, not only of his own works, but of the still drier ones written in his refutation. Those who desire this dreadful literature can find it; it has a 'disciplinary value;' but I will not even enumerate it in a footnote. The only amusing part of it is that Fechner's critics should always feel bound, after smiting his theories hip and thigh and leaving not a stick of them standing, to wind up by saying that nevertheless to him belongs the imperishable glory, of first formulating them and thereby turning psychology into an exact science, "And everybody praised the duke Why, that I cannot tell,' said he, 'But 'twas a famous victory!'" CHAPTER XIV.* ASSOCIATION. AFTER discrimination, association! Already in the last chapter I have had to invoke, in order to explain the improvement of certain discriminations by practice, the 'association' of the objects to be distinguished, with other more widely differing ones. It is obvious that the advance of our knowledge must consist of both operations; for objects at first appearing as wholes are analyzed into parts, and objects appearing separately are brought together and appear as new compound wholes to the mind. Analysis and synthesis are thus the incessantly alternating mental activities, a stroke of the one preparing the way for a stroke of the other, much as, in walking, a man's two legs are alternately brought into use, both being indispensable for any orderly advance. The manner in which trains of imagery and consideration follow each other through our thinking, the restless flight of one idea before the next, the transitions our minds make between things wide as the poles asunder, transitions which at first sight startle us by their abruptness, but which, when scrutinized closely, often reveal intermediating links of perfect naturalness and propriety-all this magical, imponderable streaming has from time immemorial excited the admiration of all whose attention happened to be caught by its omnipresent mystery. And it has furthermore challenged the race of philosophers to banish something of the mystery by formulating the process in simpler terms. The problem which the philosophers have set themselves is that of ascertaining principles of connection between the thoughts which thus appear to sprout one out *The theory propounded in this chapter, and a good many pages of the text, were originally published in the Popular Science Monthly for March, 1880. of the other, whereby their peculiar succession or coexistence may be explained. But immediately an ambiguity arises which sort of connection is meant? connection thought-of, or connection between thoughts? These are two entirely different things, and only in the case of one of them is there any hope of finding principles.' The jungle of connections thought of can never be formulated simply. Every conceivable connection may be thought of-of coexistence, succession, resemblance, contrast, contradiction, cause and effect, means and end, genus and species, part and whole, substance and property, early and late, large and small, landlord and tenant, master and servant,-Heaven knows what, for the list is literally inexhaustible. The only simplification which could possibly be aimed at would be the reduction of the relations to a smaller number of types, like those which such authors as Kant and Renouvier call the 'categories' of the understanding.* According as we followed one category or another we should sweep, with our thought, through the world in this way or in that. And all the categories would be logical, would be relations of reason. They would fuse the items into a continuum. Were this the sort of connection sought between one moment of our thinking and another, our chapter might end here. For the only summary description of these infinite possibilities of transition, is that they are all acts of reason, and that the mind proceeds from one object to another by some rational path of connection. The trueness of this formula is only equalled by its sterility, for psychological purposes. Practically it amounts to simply referring the inquirer to the relations between facts or things, and to telling him that his thinking follows them. But as a matter of fact, his thinking only sometimes. follows them, and these so-called 'transitions of reason are far from being all alike reasonable. If pure thought runs all our trains, why should she run some so fast and some so slow, some through dull flats and some through * Compare Renouvier's criticism of associationism in his Essais de Critique générale, Logique, II. p. 493 foll. gorgeous scenery, some to mountain-heights and jewelled mines, others through dismal swamps and darkness?—and run some off the track altogether, and into the wilderness of lunacy? Why do we spend years straining after a certain scientific or practical problem, but all in vainthought refusing to evoke the solution we desire? And why, some day, walking in the street with our attention miles away from that quest, does the answer saunter into our minds as carelessly as if it had never been called forsuggested, possibly, by the flowers on the bonnet of the lady in front of us, or possibly by nothing that we can discover? If reason can give us relief then, why did she not do so earlier? The truth must be admitted that thought works under conditions imposed ab extra. The great law of habit itself -that twenty experiences make us recall a thing better than one, that long indulgence in error makes right thinking almost impossible-seems to have no essential foundation in reason. The business of thought is with truth-the number of experiences ought to have nothing to do with her hold of it; and she ought by right to be able to hug it all the closer, after years wasted out of its presence. The contrary arrangements seem quite fantastic and arbitrary, but nevertheless are part of the very bone and marrow of our minds. Reason is only one out of a thousand possibilities in the thinking of each of us. Who can count all the silly fancies, the grotesque suppositions, the utterly irrelevant reflections he makes in the course of a day? Who can swear that his prejudices and irrational beliefs constitute a less bulky part of his mental furniture than his clarified opinions? It is true that a presiding arbiter seems to sit aloft in the mind, and emphasize the better suggestions into permanence, while it ends by droopping out and leaving unrecorded the confusion. But this is all the difference. The mode of genesis of the worthy and the worthless seems the same. The laws of our actual thinking, of the cogitatum, must account alike for the bad and the good materials on which the arbiter has to decide, for wisdom and for folly. The laws of the arbiter, of the cogitandum, of what we ought to think, are to the former as the |