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struction, the lessons of pleasure and pain, and of experience generally, and reasoning from means to ends, etc.

We reach, therefore, the following scheme:

Ontogenetic Modifications.

Ontogenic Agencies. 1. Physico-genetic.

1. Mechanical. 2. Neuro-genetic.

2. Nervous. 3. Psycho-genetic.

3. Intelligent.

Imitation.
Pleasure and pain.

Reasoning. Now it is evident that there are two very distinct questions which come up as soon as we admit modifications of function and of structure in ontogenetic development: first, there is the question as to how these modifications can come to be adaptive in the life of the individual creature. Or in other words: What is the method of the individual's growth and adaptation as shown in the well known law of “use and disuse ?" Looked at functionally, we see that the organism manages somehow to accommodate itself to conditions which are favorable, to repeat movements which are adaptive, and so to grow by the principle of use. This involves some sort of selection, from the actual ontogenetic variations, of certain ones—certain functions, etc. Certain other possible and actual functions and structures decay from disuse. Whatever the method of doing this may be, we may simply, at this point, claim the law of use and disuse, as applicable in ontogenetic development, and apply the phrase, “ Organic Selection,” to the organism's behavior in acquiring new modes or modifications of adaptive function with its influence of structure. The question of the method of “ Organic Selection ” is taken up below (IV); here, I may repeat, we simply assume what every one admits in some form, that such adaptations of function—"accommodations” the psychologist calls them, the processes of learning new movements, etc.do occur. We then reach another question, second; what place these adaptations have in the general theory of development.

Effects of Organic Selection.-First, we may note the results of this principle in the creature's own private life.

1. By securing adaptations, accommodations, in special circumstances the creature is kept alive (ref. 2, 1st ed., pp. 172 ff.). This is true in all the three spheres of ontogenetic variation distinguished in the table above. The creatures which can stand the “storm and stress” of the physical influences of the environment, and of the changes which occur in the environment, by undergoing modifications of their congenital functions or of the structures which they get congenitallythese creatures will live; while those which cannot, will not. In the sphere of neurogenetic variations we find a superb series of adaptations by lower as well as higher organisms during the course of ontogenetic development (ref. 2, chap. ix). And in the highest sphere, that of intelligence (including the phenomena of consciousness of all kinds, experience of pleasure and pain, imitation, etc.), we find individual accommodations on the tremendous scale which culminates in the skilful performances of human volition, invention, etc. The progress of the child in all the learning processes which lead him on to be a man, just illustrates this higher form of ontogenetic adaptation (ref. 2, chap. x-xiii).

All these instances are associated in the higher organisms, and all of them unite to keep the creature alive.

2. By this means those congenital or phylogenetic variations are kept in existence, which lend themselves to intelligent, imitative, adaptive, and mechanical modification during the lifetime of the creatures which have them. Other congenital variations are not thus kept in existence. So there arises a more or less widespread series of determinate variations in each generation's ontogenesis (ref. 3, 4, 5).3

3" It is necessary to consider further how certain reactions of one single organism can be selected so as to adapi the organism better and give it a life history. Let us at the outset call this process “Organic Selection” in contrast with the Natural Selection of whole organisms.

If this (natural selection) worked alone, every change in the environment would weed out all life except those organisms, which by accidental variation reacted already in the way demanded by the changed conditions-in every case new organisms showing variations, not, in any case, new elements of life-history in the old organisms. In order to the latter we would have to conceive . . . some modification of the old reactions in an or. ganism through the influence of new conditions. .. We are, accordingly, left to the view that the new stimulations brought by changes in the environment

The further applications of the principle lead us over into the field of our second question, i. e., phylogeny.

II.

Phylogeny : Physical Heredity.The question of phylogenetic development considered apart, in so far as may be, from that of heredity, is the question as to what the factors really are which show themselves in evolutionary progress from generation to generation. The most important series of facts recently brought to light are those which show what is called “determinate variation” from one generation to another. This has been insisted on by the paleontologists. Of the two current theories of heredity, only one, Neo-Lamarkism-by means of its principle of the inheritance of acquired characters-has been able to account for this fact of determinate phylogenetic change. Weismann admits the inadequacy of the principle of natural selection, as operative on rival organisms, to explain variations when they are wanted or, as he puts it, “the right variations in the right place(Monist, Jan., '96).

I have argued, however, in detail that the assumption of determinate variations of function in ontogenesis, under the principle of neurogenetic and psychogenetic adaptation, does away with the need of appealing to the Lamarkian factor. In the case i. g., of instincts, “if we do not assume consciousness, then natural selection is inadequate; but if we do assume consciousness, then the inheritance of acquired characters is unnecessary” (ref. 5).

“The intelligence which is appealed to, to take the place of instinct and to give rise to it, uses just these partial variations which tend in the direction of the instinct; so the intelligence supplements such partial co-ordinations, makes them functional, and so keeps the creature alive. In the phrase of Prof. themselves modify the reactions of an organism.

The facts show that individual organisms do acquire new adaptations in their lifetime, and that is our first problem. If in solving it we find a principle which may also serve as a principle of race-development, then we may possibly use it against the 'all sufficiency of natural selection' or in its support” (ref. 2, 1st. ed., pp. 175-6.)

Lloyd Morgan, this prevents the incidence of natural selection.' So the supposition that intelligence is operative turns out to be just the supposition which makes use-inheritance unnecessary. Thus kept alive, the species has all the time necessary to perfect the variations required by a complete instinct. And when we bear in mind that the variation required is not on the muscular side to any great extent, but in the central brain connections, and is a slight variation for functional purposes at the best, the hypothesis of use-inheritance becomes not only unnecessary, but to my mind quite superfluous” (ref. 4, p. 439). And for adaptations generally, “the most plastic individuals will be preserved to do the advantageous things for which their variations show them to be the most fit, and the next generation will show an emphasis of just this direction in its variations” (ref. 3, p. 221).

We get, therefore, from Organic Selection, certain results in the sphere of phylogeny:

1. This principle secures by survival certain lines of determinate phylogenetic variation in the directions of the determinate ontogenetic adaptations of the earlier generation. The variations which were utilized for ontogenetic adaptation in the earlier generation, being thus kept in existence, are utilized more widely in the subsequent generation (ref. 3, 4). Congenital variations, on the one hand, are kept alive and made effective by their use for adaptations in the life of the individual; and, on the other hand, adaptations become congenital by further progress and refinement of variation in the same lines of function as those which their acquisition by the individual called into play. But there is no need in either case to assume the Lamarkian factor” (ref. 3). And in cases of conscious adaptation : “ We reach a point of view which gives to organic evolution a sort of intelligent direction after all; for of all the variations tending in the direction of an adaptation, but inadequate to its complete performance, only those will be supplemented and kept alive which the intelligence ratifies and uses. The principle of 'selective value' applies to the others or to some of them. So natural selection kills off the others; and the future development at each stage of a species' development must be in the directions thus ratified by intelligence. So also with imitation. Only those imitative actions of a creature which are useful to him will survive in the species, for in so far as he imitates actions which are injurious he will aid natural selection in killing himself off. So intelligence, and the imitation which copies it, will set the direction of the development of the complex instincts even on the Neo-Darwinian theory; and in this sense we may say that consciousness is a 'factor?” (ref. 4).

2. The mean of phylogenetic variation being thus made more determinate, further phylogenetic variations follow about this mean, and these variations are again utilized by Organic Selection for ontogenetic adaptation. So there is continual phylogenetic progress in the directions set by ontogenetic adaptation (ref. 3, 4, 5). “The intelligence supplements slight co-adaptations and so gives them selective value ; but it does not keep them from getting farther selective value as instincts, reflexes, etc., by farther variation " (ref. 5). “The imitative function, by using muscular co-ordinations, supplements them, secures adaptations, keeps the creature alive, prevents the incidence of natural selection,' and so gives the species all the time necessary to get the variations required for the full instinctive performance of the function” (ref. 4). But,“ Conscious imitation, while it prevents the incidence of natural selection, as has been seen, and so keeps alive the creatures which have no instincts for the performance of the actions required, nevertheless does not subserve the utilities which the special instincts do, nor prevent them from having the selective value of which Romanes speaks. Accordingly, on the more general definition of intelligence, which includes in it all conscious imitation, use of maternal instruction, and that sort of thing—no less than on the more special definition-we still find the principal of natural selection operative" (ref. 5).

3. This completely disposes of the Lamarkian factor as far as two lines of evidence for it are concerned. First, the evidence drawn from function, “ use and disuse,” is discredited ; since by “organic selection,” the reappearance, in subsequent generations, of the variations first secured in ontogenesis is ac

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