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Italy, when she obtained liberty of conscience, still maintained the traditions and tenets of the Catholic religion; as, even while relinquishing most of the modes of applying ideal philosophy, she has still preserved intact its essential thought, so the acquisitions which modern science has made of late she will gradually assimilate according to her own way of thinking.

This characteristic development will react on her institutions and customs. In issuing from the revolutionary phase, which was a rude shock to education and to the sense of national and individual responsibility, men will return to a normal state of things, and forget a phase which was in some respects as disastrous as the absolutism which preceded it. It is difficult to say what will be the fixed and normal point of this evolution, but it will certainly conform to the traditions of the past. There is a line of demarcation between the Græco-Latin and Teutonic peoples which will probably never wholly disappear. The first set before them art and the ideal, the second nature and reality. The Germans have indeed also their ideals, and they have assimilated the arts with the same diligence and with greater success than the Italians now apply themselves to the study of nature and reality. And just as the Italians have sometimes nearly ceased to seek art and the ideal, so the Germans have at other times cared less for nature and reality. But sooner or later a preponderating force leads both men and peoples back into their own orbit and proper sphere of action.

This power of education and assimilation exerts a great influence on their future, and corrects defects and excesses. As the influence and example of the Latins has civilised the Teutonic nations, so has the German influence been of use to the Latins. And in the struggle for existence, which no longer takes the form of slaughter and ferocity, that nation or individual will be most successful which can assimilate the qualities of others while retaining his own.

VOL. XVI.-No. 91.

G G

F. NOBILI-VITELLESCHI.

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THE

DARWINIAN THEORY OF INSTINCT.

'GAVEST thou the goodly wings unto the peacocks? or wings and feathers unto the ostrich? which leaveth her eggs in the earth, and warmeth them in dust, and forgetteth that the foot may crush them, or that the wild beast may break them. . . . Because God hath deprived her of wisdom, neither hath He imparted to her understanding.'

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This is the oldest theory of instinct. The writer of that sublime monument of literary power in which it occurs observed a failure of instinct on the part of the ostrich, and forthwith attributed the fact to neglect on the part of the Deity; the implication plainly being that in all cases where instinct is perfect, or completely suited to the needs of the animal presenting it, the fact is to be attributed to a God-given faculty of wisdom. This, I say, is the oldest theory of instinct, and I may add that until within the past twenty-five years it has been the only theory of instinct. I think, therefore, I ought to begin by explaining that this venerable and time-honoured theory is a purely theological explanation of the ultimate source of instinct, and therefore cannot be affected by any scientific theory as to the proximate causes of instinct. It is with such a theory alone that we shall here be concerned. When giants build, men must bring the stones.' For the past eight or ten years I have been engaged in elaborating Mr. Darwin's theories in the domain of psychology, and I cannot allude to my own work in this connection without expressing the deep obligations under which I lie to his ever ready and ever generous assistance-assistance rendered not only in the way of conversation and correspondence, but also by his kindness in making over to me all his unpublished manuscripts, together with the notes and clippings which he had been making for the past forty years in psychological matters.. I have now gone carefully through all this material, and have published most of it in my work on Mutual Evolution in Animals.' I allude to this work on the present occasion in order to observe that, as it has so recently come out, I shall feel myself entitled to assume that few have read it; and therefore I shall not cramp my remarks by seeking to avoid any of the facts or arguments therein contained.

As there are not many words within the compass of our language which have had their meanings less definitely fixed than the word 'instinct,' it is necessary that I should begin by clearly defining the sense in which I shall use it.

In general literature and conversation we usually find that instinct is antithetically opposed to reason, and this in such wise that the mental operations of the lower animals are termed instinctive; those of man are termed rational. This rough and ready attempt at psychological classification has descended to us from remote antiquity, and, like kindred attempts at zoological classification, is not a bad one so far as it goes. To divide the animal kingdom into beasts, fowls, fish, and creeping things, is a truly scientific classification as far as it goes, only it does not go far enough for the requirements of more careful observation; that is to say, it only recognises the more obvious and sometimes only superficial differences, while it neglects the more hidden and usually more important resemblances. And to classify all the mental phenomena of animal life under the term 'instinct,' while reserving the term reason' to designate a mental peculiarity distinctive of man, is to follow a similarly archaic method. It is quite true that instinct preponderates in animals, while reason preponderates in man. This obvious fact is what the world has always seen, just as it saw that flying appeared to be distinctive of birds, and creeping of reptiles. Nevertheless, a bat was all the while a mammal and a pterodactyl was not a bird; and it admits of proof as definite that what we call instinct in animals occurs in man, and that what we call reason in man occurs in animals. This, I mean, is the case if we wait to attach any definition to the words which we employ. It is quite evident that there is some difference between the mind of a man and the mind of a brute, and if without waiting to ascertain what this difference is, we say that it consists in the presence or absence of the faculty of reason, we are making the same kind of mistake as when we say that the difference between a bird and a mammal consists in the presence or absence of the faculty of flying. Of course, if we choose, we may employ the word 'reason' to signify all the differences taken together, whatever they may be; and so, if we like, we may use the word 'flying.' But in either case we shall be talking nonsense, because we should be divesting the words of their meaning, or proper sense. The meaning of the word reason' is the faculty of ratiocinationthe faculty of drawing inferences from a perceived equivalency of relations, no matter whether the relations involve the simplest mental perceptions, or the most abstruse mathematical calculations. And in this, the only real and proper sense of the word, reason is not the special prerogative of man, but occurs through the zoological scale at least as far down as the articulata.

What then is to be our definition of instinct?

First of all, instinct involves mental operation, and therefore implies consciousness. This is the point which distinguishes instinct from reflex action. Unless we assume that a new-born infant, for example, is conscious of sucking, it is as great a misnomer to term its adaptive movements in the performance of this act instinctive, as it would be similarly to term the adaptive movements of its stomach subsequently performing the act of digestion.

Next, instinct implies hereditary knowledge of the objects and relations with respect to which it is exercised; it may therefore operate in full perfection prior to any experience on the part of the individual. When the pupa of a bee, for instance, changes into an imago, it passes suddenly from one set of experiences to another, the difference between its previous life as a larva and its new life as an imago being as great as the difference between the lives of two animals belonging to two different sub-kingdoms; yet as soon as its wings are dry it exhibits all the complex instincts of the mature insect in full perfection. And the same is true of the instincts of vertebrated animals, as we know from the researches of the late Mr. Douglas Spalding and others.

Again, instinct does not imply any necessary knowledge of the relations between means employed and ends attained. Such knowledge may be present in any degree of distinctness, or it may not be present at all; but in any case it is immaterial to the exercise of the instinct. Take, for example, the instinct of the Banbex. This insect brings from time to time fresh food to her young, and remembers very exactly the entrance to her cell, although she has covered it with sand, so as not to be distinguishable from the surrounding surface. Yet M. Fabre found that if he brushed away the earth and the underground passage leading to the nursery, thus exposing the contained larva, the parent insect was quite at a loss, and did not even recognise her own offspring. It seemed as if she knew the doors, nursery, and the passage, but not her child.'

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Lastly, instinct is always similarly manifested under similar circumstances by all the individuals of the same species. And, it may be added, these circumstances are always such as have been of frequent occurrence in the life-history of the species.

Now in all these respects instinct differs conspicuously from every other faculty of mind, and especially from reason. Therefore, to gather up all these differentice into one definition, we may say that instinct is the name given to those faculties of mind which are concerned in consciously adaptive action, prior to individual experience, without necessary knowledge of the relation between means employed and ends attained; but similarly performed under similar and frequently recurring circumstances by all the individuals of the same species.

Such being my definition of instinct, I shall now pass on to

consider Mr. Darwin's theory of the origin and development of instincts.

Now, to begin with, Mr. Darwin's theory does not, as many suppose that it does, ascribe the origin and development of all instincts to natural selection. This theory does, indeed, suppose that natural selection is an important factor in the process; but it neither supposes that it is the only factor, nor even that in the case of numberless instincts it has had anything at all to do with their formation. Take, for example, the instinct of wildness, or of hereditary fear as directed towards any particular enemy-say man. It has been the experience of travellers who have first visited oceanic islands without human inhabitants and previously unvisited by man, that the animals are destitute of any fear of man. Under such circumstances the birds have been known to alight on the heads and shoulders of the newcomers, and wolves to come and eat meat held in one hand while a knife was held ready to slay them with the other. But this primitive fearlessness of man gradually passes into an hereditary instinct of wildness, as the special experiences of man's proclivities accumulate; and as this instinct is of too rapid a growth to admit of our attributing it to natural selection (not one per cent. of the animals having been destroyed before the instinct is developed), we can only attribute its growth to the effects of inherited observation. In other words, just as in the lifetime of the individual, adjustive actions which were originally intelligent may by frequent repetition become automatic, so in the lifetime of the species, actions originally intelligent may, by frequent repetition and heredity, so unite their efforts on the nervous system that the latter is prepared, even before individual experience, to perform adjustive actions mechanically which, in previous generations, were performed intelligently. This mode of origin of instincts has been appropriately called the 'lapsing of intelligence,' and it was fully recognised by Mr. Darwin as a factor in the formation of instinct.

The Darwinian theory of instinct, then, attributes the evolution of instincts to these two causes acting either singly or in combination -natural selection and lapsing intelligence. I shall now proceed to adduce some of the more important facts and considerations which, to the best of my judgment, support this theory, and show it to be by far the most comprehensive and satisfactory explanation of the phenomena which has hitherto been propounded.

That many instincts must have owed their origin and development to natural selection exclusively is, I think, rendered evident by the following general considerations::

(1) Considering the great importance of instincts to species, we are prepared to expect that they must be in large part subject to the influence of natural selection. (2) Many instinctive actions are performed by animals too low in the scale to admit of our supposing that the adjustments which are now instinctive can ever have been

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