Having, in the previous chapters, pointed out how greater length of life and higher degree of life accompany increased speciality and increased generality of correspondences, it is needless to dwell on the fact that where both these unite in producing correspondences of increased complexity, the like result must happen. It may be added, however, that not only is this true of the more complex intellectual guidance which, through the medium of Science, advances the Arts; but it is true of the more complex emotional guidance which, by making social order possible, contributes to the greater individual safety that social order brings.
CHAPTER IX.
THE CO-ORDINATION OF CORRESPONDENCES.
§ 166. FULLY to comprehend the increase of the corre- spondence between the organism and its environment, in speciality, in generality, and in complexity, it is requisite to contemplate the facts under yet another aspect. "We imust look at the general conditions by fulfilment _of wliicli \ these more elaborate adjustments of inner to outer rela- tions are made possible. The performance of a compound action in response to a compound impression, implies some- thing more than a susceptibility to each of the several elements constituting the compound impression, and a power to effect each of the several motions constituting tne compound action. It implies that the constituent sensa- tions and contractions shall be combined after a particular manner — shall be co-ordinated; and the perfection of the correspondence will vary as the perfection of the co- ordination.
Let us take first a simple case, as that of the actions needed for escape from an enemy. When we rise from creatures in which the motion of some conspicuous adjacent object is responded to by random muscular movements, to T-reatures in which the muscular movements are such as to carry the body away from the dangerous object; we rise to an adjustment of at least two joined relations in the organism to two joined relations in the environment.
THE CO-ORDINATION OF CORRESPONDENCES. 371 The strong visual impression produced "by the adjacent moving object being the stimulus to activity; then, that the activity may be of the right kind, such modification of the impression as depends on the direction of the body in space must be recognized, and the activity modified accordingly. The impression which indicates dangerousness and thai which indicates position, must together control the motor changes; and the control must consist in so ordering their respective amounts that the resulting motion may carry the organism away from the source of danger, When distance as well as direction becomes cognizable, and when the colour and shape of the object are distinguished as well as its mass, the stimulus is composed of a much greater number of ele- ments, united after a special manner; and the more rapid,, skilful, and varied the consequent actions become, the more elaborate and more perfect are the implied combinations of motor changes. While just as a wrong combination of motor changes involves a fall or other failure of action, so, a wrong combination of the separate stimuli entails a mis- taken perception.
Space need not be occupied in tracing up these simple kinds of co-ordination. It is obvious that throughout the series of increasingly-compound perceptions, including even the recognitions of localities by identification of surrounding objects, the constituents of each perception co-operate after a particular manner; and that, as especially seen in this case of localities, it is only in virtue of a definite relation- ship among them that a definite perception is possible. No less obvious is it that the increasingly- complex actions by which higher creatures achieve their ends, succeed only in as far as the muscular contractions implied are fitly regu- lated in their order, their amounts, and their modes of con- junction.
§ 167. Advancing from these cases in which the directive stimuli, though heterogenous, are made up of elements that 372 GENEKAL SYNTHESIS.
are simultaneously present to the senses, to the cases in which some of their elements are present to the senses and some not, we meet with a sensory co-ordination of a new and higher order. And where the responding motions, no longer°occurring as an inseparable group, are divided by intervals that vary according to circumstances, we see a parallel progress in motor co-ordination. A creature which when pursued runs to its burrow, supplies us with an in- stance ol the one; while an instance of the other occurs in any process which, like the building of a nest, is effected by instalments variously interrupted by other pro- cedures. From the stage in which a single past impression unites with many present ones to compose a special stimulus, and in which the action completed at in- tervals is tolerably homogeneous in character, the advance is towards a union of many past impressions with present ones, and towards a kind of action increasingly heteroge- neous in its instalments, as well as in the manner of their succession. In men's daily transactions, the complex sights, sounds, and muscular sensations, serving for im- mediate guidance, are co-ordinated with recollections of the persons, places, things, events, to which those transactions refer; and one who mistakes the hour at which certain business is to be done with certain people at a certain office, shows us how a failure arises from imperfect co- ordination of the past and present impressions constituting the directive stimulus. The operations by which wheat is sown, weeded, reaped, stacked, thrashed, winnowed, taken to market, and sold, compose a series of widely-different groups of actions (each consisting of many minor groups), divided by dissimilar and variable intervals, all combined to achieve a single end; and to achieve it they must be a3justed in a particular manner. The elaborateness of these advanced correspondences in which time past, time present, and time future are alike involved, and which have simultaneous reference to sundry places in space, is an THE CO-ORDINATION OF CORftESPONDENCES. 373 elaborateness measured by the number of past impressions compounded with present ones, and past actions coin- pounded with present ones. But the all-essential thing is the definiteiiess with which the combination is adapted to the combination of external circumstances — the goodness of the co-ordination.
§ 168. A still higher species of co-ordination growing imperceptibly out of the last, and vaguely seen even m the illustrations just given, involves not simply the union of past with present specialities, but the union of generalities with both. The perception received yesterday when the barometer stood at " Fair/' together with the perception received to-day, when it stands at (C Change/5 bring no con- clusion unless joined to the generalization that a fall of the mercurial column commonly indicates rain. Nay, before a true inference can be drawn for to-morrow's guidance, these data must be joined with the further generalization, that only when the air is charged with water to a certain degree is rain indicated by a falling barometer. In other cases, as in that of a physician prescribing for his patient, many remembered observations of bygone symptoms, many ob- servations of existing ones, and many general truths serving to interpret the changes that have taken place, must enter into that directive process which terminates in an appro- priate course of treatment.
But the most developed form of co-ordination is that exhibited by quantitative science. In this, not only must .ft" specialities be combined with generalities after a perfectly definite manner; but there must be perfect definiteness in each constituent of the combination. The perceptions by which the data are obtained must have their elements so exactly co-ordinated as to give measured results. The law's of dependsnce must be so known that they can be expressed numerically. And the process by which, out of data and laws, the prevision is finally evolved, must have each step 374 GENERAL SYNTHESIS.
united with preceding and succeeding steps in a mode that is quite specific. An estimate of the horse-power required to move a given steam-vessel at a specified speed, involves these general truths:— that the resistance encountered by a body moving through fluid varies as the square of the velocity; that the area opposed by a vessel to the water varies as the squares of its dimensions; that the ton- nage varies as the cubes of the dimensions; with sundry others. Particular forces,, weights, specific gravities, lengths, breadths, depths, have to be combined with these o-eneral truths, each with each; and the results have to be farther combined after particular modes. If one of the generalities be applied to the wrong specialities — if the formula for resistance be brought to bear, not on the figures representing sectional area, but on those representing ton- nage— if the data be inexact, or the principles be misunder- stood, or the calculation be erroneously performed, that is — if there be imperfect co-ordination of the various mental acts involved; a false conclusion is reached: there is a failure of cognition: the internal relations are not rightly adjusted to external ones, as is proved by the result.
It will farther elucidate both this doctrine of co-ordina- tion and the general doctrine of correspondence, if we con- sider how, for the perfect adjustment of inner to outer relations, there must exist in the first, elements and changes symbolizing all the essential elements and changes in the last. Undeveloped life is led by associations among some of the superficial attributes of things. Developed life is led by associations among those fundamental attributes on which the actions of the things depend. There is no in- variable connexion between a loud sound and an adjacent enemy; and hence, creatures in which one of these serves as an index to the other, are often wrong in the adjustments of their internal relations to external ones. But the con- nexion between linear dimensions and solid contents, or between velocity and momentum,, is constant, and therefore - THE CO-ORDINATION OF CORBESPONDENCES. 375 affords infallible guidance. Before this infallible guidance can be had, however, all the elements of the relation must be known. Whenever a group of inner relations, or cogni- tion, is completely conformed to a group of outer relations, or phenomenon, by a rational process — whenever there is what we call an understanding of the phenomenon — the composition of the phenomenon is, in a sense, paralleled by the composition of the cognition. The law that the momentum of a moving body varies as its velocity mul- tiplied into its weight, cannot be known until there exist in the mind conceptions answering to momentum, velocity, and weight; it cannot be known until there exist in the mind ideas of time, space, and matter, without which velo- city and momentum are inconceivable; it cannot be known until there are processes of thought answering to those quantitative connexions which " varies as " and " multiplied into " indicate -, nay, the law cannot be known until the states of consciousness symbolizing time and space, are so co-ordinated as to symbolize velocity; nor until the states of consciousness symbolizing velocity and weight are so co-ordinated as to symbolize momentum; nor until these three are again co-ordinated according to those laws of relation implied by "varies as" and "multiplied into." That is, every attribute necessarily involved in the pheno- menon must have its internal representative; and the several laws of dependence among these attributes must be each represented by some constant relation among their representatives.
These facts bring out into yet clearer light, the general doctrine variously presented in the preceding chapters. That in these highest manifestations of Life produced by the cul- ture of civilization — these quantitative previsions which im- ply such intense vital action while they so greatly subserve self-preservation by facilitating commerce and the arts — there should be this elaborate and complete co-ordination of inner relations to symbolize outer relations, serves as a 376 GENERAL SYNTHESIS.
crowning illustration of the truths, that Life is tne main- tenance of a correspondence between the organism and its environment, and that the degree of Life varies as the degree of correspondence. The many proofs which have been given that the life and the correspondence advance hand in hand,, become doubly conclusive on finding that the two culminate together- CHAPTER X.
THE INTEGRATION OF COIiRESPONDENCES.
§ 169. There is one more point of view from which tlie phenomena of Life must be contemplated. We have to note how,, out of co-ordination, there grows up integration. Compound impressions, as well as the compound motions guided by them,, continually approach in their apparent characters to simple impressions and simple motions. The co-ordinated elements of any stimulus or of any act ever tend towards union; and eventually become distinguishable from one another only by analysis. Further, the connexion between stimulus and act also becomes constantly closer; so that at last they seem two sides of the same change.
Only by virtue of this law do the higher kinds of corre- spondence become possible. In its absence, complex im- pressions could not generate complex actions with the needful rapidity; nor would there be time for that immense multiplicity of adjustments which developed life displays. If the two organic changes which constitute sensation and motion, did not, in superior creatures, follow with greater rapidity than the withdrawal of a snail into its shell follows the touch of its horn, all those correspondences with the environment which imply any quickness of adaptatiftn would be impracticable. If the period that elapses between the gaze of a young child at a stranger and the fit of crying that follows (a period during which the component visual 878 GENERAL SYNTHESIS.
impressions are being co-ordinated), were habitually paral- leled in the perceptions of adults— if compound cognitions were not formed, and the appropriate operations produced by them,, in periods incomparably briefer,, human life would cease.
The necessity for this progressive integration will be most clearly understood if, regarding sensations as symbols and perception as the interpretation of groups of symbols,, we observe what takes place with verbal symbols and the meanings they convey. Where intelligence is but little evolved,, a single sensation,, as of scent, serves the organism for an index of the combined attributes with which such scent is connected • and similarly, in undeveloped language a simple sound is used to indicate a complex idea. In either case, this system answers very well within narrow limits. But a large increase in the number of correspon- dences requires another system. By scent, only some objects can be distinguished: many are scentless. Simple sounds and marks are too few in number to represent any considerable variety of ideas. Hence, in either case, compound symbols must be used before there can be a great multiplication of the correspondences. Things that are without odour, and things that are alike in odour, can be divided into sub-classes when impressions of colour and size, as well as of scent, can be appreciated. And when simple sounds are endlessly modified by articulations, and simple signs are replaced by composite signs, it becomes possible verbally to indicate an infinity of objects, acts, qualities, &c. But on what condition only does this more elaborate language become serviceable? or, to confine the attention to one division of it— What is required before composite written signs can supplant simple written signs? It is required that the constituent elements of each com- posite sign shall be so efficiently co-ordinated, so rapidly united in the act of perception, so integrated, as to become practically one. Had the letters that make up every word THE INTEGRATION OE CORRESPONDENCES. 379 to "be separately identified, as tlie child identifies them when learning to read,, the system would be of little or no use. Able, though it might be, to express with precision all verbal articulations, it could never compete with the limited system of simple signs, did it remain thus cumbrous in its application. Similarly with the primordial language of perception. If the several colours, size, shape, motion, direction, and distance, of an object, had to be successively identified by the creature perceiving it — if the object had to be spelled out in this deliberate fashion; the method of recognition by combined sensations would yield in utility to the method of recognition by a single sensation. Universal in its powers, it would yet be too slow of use to satisfy the requirements. In both cases, however, the pro- gressive integration of the component correspondences removes this difficulty, by practically reducing the com- pound signs to simple ones. A word made up of a dozen letters comes eventually to be recognized as quickly as a single letter. The host of impressions involved in the perception of a carriage, seemingly take no more time to receive and interpret than a single sound or taste. And.thus there is immeasurable gain in the speciality of the correspondences, without loss in their rapidity. Let us glance at the results.
§ 170. It is needless to dwell on the apparent simul- taneity with which the many visual sensations given us by an object, arouse those ideas of tangible extension, of resist- ance, of texture, with which experience has joined them: the entire group of sensations and the inferences drawn from them, seeming to constitute but a single state of con- sciousness. Nor is it requisite to do more than indicate the exceeding precision with which the most complex assem- blages • of these symbols are instantly distinguished from nearly identical assemblages; as shown in our ability to recognize by a single look, a particular person, and even his 380 GENERAL SYNTHESIS.
particular mental state. But to convey a vivid idea of the manner in which, this integration of correspondences sub- serves the perceptions, it will be well to describe an experi- ment showing its extreme strength and rapidity.
We judge of distance by at least three separate indica- tions. When the observed object is known to us, the angle it subtends, or, rather, the space which its image covers on the retina, aids in the estimate. The particular focal adjust- ments which the eyes undergo to obtain distinct vision, and which are accompanied by certain muscular sensations, assist. And the muscular sensations accompanying due convergence of the visual axes, supply a third evidence. In ordinary vision these indications agree. But by that ingenious in- strument of Professor Wheatstone's invention — the Pseudo- scope — the last two are made to contradict each other. The muscular actions by which the visual axes are adjusted being the more marked, and accompanied by the stronger sensations, give the preponderating evidence; and the result is that when looked at through the Pseudoscope, convex objects seem concave and concave objects seem convex. By particular management, however — that is, by adding to the evidence from focal adjustment some further evidence — the verdict of consciousness may be suddenly reversed. If, after contemplating the inside of a cup and wondering at its apparent convexity, the cup be turned laterally little by little, so that the outside gradually comes into view and the opening grows more elliptical, there presently arrives a time when the perception all at once changes, and the cup is seen under its ordinary aspect. Now the fact here to be remarked as so significant, is the impossibility of any inter- mediate or hesitating judgment. Notwithstanding the con- flict of evidence, there is, save at the moment of change, a definite perception either of concavity or of convexity. The perception is not incomplete or obscure, but perfectly distinct. The preponderating impressions dragging with them all those other impressions which they habitually T1TE INTEGRATION OF CORRESPONDENCES. 381 imply, produce the same effect as though, these other im- pressions were actually received, instead of the opposite ones being received. The co-ordinated sensations have become ao integrated that no considerable part of the group can be present to consciousness without the whole group being present.
With the executive processes as well as with the directive processes, this integration takes place. A long-employed combination of muscular actions is at last almost undecom- posable. The tricks of walk, of attitude, of manual action, which children acquire, and of which it is so difficult to break them, furnish examples. We have another example in stammering, which, commencing as it often does with imitation, becomes, when once established, next to incur- able. So, too, is it with peculiarities of handwriting. The motions of the fingers having by years of practice been co- ordinated in a particular manner, cannot be otherwise co- ordinated without a degree of labour to which few are equal. Though, by moving them slowly and with attention, the fingers may be made to produce differently- formed letters; yet, on the attention being relaxed and the usual speed resumed, the letters re-acquire their old characters. Simi- larly in all handicrafts, chains of perpetually-repeated mus- cular actions, however complex, eventually approximate in rapidity and ease to simple motions; and, at the same time, cease to be capable of modified adjustment — tend more and more to produce one another automatically — grow insepa- rable— become integrated.
Similar integrations go on between cognitions and the operations guided by them. In the child learning to walk, or to lay hold of a neighbouring object, or to pronounce a word, there is a deliberate and conscious modification of the motions in obedience to the sensations. But in after-yeafs the various muscular adjustments by which, from minute to minute, the intentions are fulfilled, follow the will instanta- neously and without oversight of the intellect. While 382 GENERAL SYNTHESIS.
absorbed in gossip, the seamstress makes stitch, after stitch by a co-ordination of sensations and actions that has become next to instinctive. When deep in thought— " absent in mind/' as the phrase is — the occurrence of particular per- ceptions will often be unconsciously followed by the actions appropriate to them: sometimes with ludicrous effect. The start on one side caused by a loud noise close at hand, or the throwing out of the arms to regain the balance after having slipped, shows us how directive and executive pro- cesses, originally quite distinct, come to be so united that one follows the other not only instantly and without voli- tion, but often without the possibility of prevention. Even where the impressions and motions are both extremely com- plex, the law may be traced; witness the feats of a skilful billiard-player. In one of his strokes we see the relative positions of the three balls to one another, to the cushions, and to the pockets, all united into a complex visual impres- sion co-ordinated with the greatest nicety; we see the direc- tion of the cue, its adjustment to the ball, the strength of its impact, and the quality of its impact, all accurately modi- fied to suit the requirements; and we see that by long habit the compound impression has been so united with the com- pound action, that the one follows the other almost mecha- nically. Wo reasoning or calculation is required; or, indeed, is permissible. For it is notorious that in games of skill, any lengthened consideration or active interference on the part of the higher faculties, almost inevitably causes a failure. The direct guidance that has been established between the constituent sensations and constituent motions, must be allowed free play; and success becomes sure in proportion as, by constant co-ordination, the combined changes become practically one change. * In all which we may perceive how that automatic cha- racter shown in the simple correspondences of inferior creatures, is gradually assumed by more complex corre- spondences— how that integration which the reflex and