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riched with the choicest collections, and the rarest curiosities of nature,* but which, from a concurrence of adverse circumstances, must have fallen into ruins, had not you, with laudable patronage, interposed, redecorated the sinking edifice, and made it once more echo to the voice of instruction and study;—here, where the genius of Science has resumed the possession of his simple throne, and is once more thronged by a numerous train of attentive votaries—here more especially may I address these observations without incurring the charge of rhapsody or extravagance.—Long may so promising an Institution flourish! soundly may it be cultivated! and of sterling value be the harvests that it produces!

There are various actions, and trains of actions, occasionally to be met with among mankind, but more frequently and more strikingly among other animals, which indicate the employment of definite means to obtain a definite end, without the intervention of that chain of thought which characterizes reason, and which have hence been ascribed to a distinct principle, that has been distinguished by the name of instinct.

Such, in the new-born infant, and, indeed, in the young of all mammalian animals, is the act of hunting out for the mother's milky food, and of sucking with a perfection which can never be acquired in subsequent life. Such is the whole process of nestling or nidification among birds; the periudi- fishes; and, among insects, the formation of the exquisite decoy-lines of the spider, and the nice masonry of the bee, and of the termes bellicosus or white ant.

The common fact admits of no dispute; the modes of accounting for it have been various, and in the utmost degree unsatisfactory. In a general survey they may be resolved into three classes: first, those hypotheses which ascribe the whole to the operation of body alone; secondly, those which ascribe it to mind alone; and, thirdly, those which derive it from a substance of a mediate nature between the two, or attribute it partly to the one and partly to the other.

In pursuing this highly interesting subject, I shall first briefly notice the principal opinions which have been offered upon it, in the order thus laid down, and point out their irrelevancy: and then propose a new theory, and explain the grounds upon which it is founded.

I. It was the opinion of Des Cartes that brutes are mere mechanical machines: that they have neither ideas nor sensation; neither pain nor pleasure; and that their outcries under punishment, and their alacrity in pursuing an enemy or devouring a meal are produced by the very same sort of force, which, exerted upon the different keys of an organ, compels its respective pipes to give forth different sounds. And a great part of the Cardinal Polignac's very elegant Latin poem, entitled Anti-Lucretius, is written in direct support of this most whimsical hypothesis. I shall, perhaps, have occasion to examine it somewhat more at large in a subsequent study: for the present it maybe sufficient to observe that, in spite of all the philosophy in the world, the coachman to this hour has whipped, and will yet continue to whip, his horses, the huntsman to halloo his hounds, and the bird-trainer to sing or whistle to his bullfinches; though if the whole were mere media*

LECTURE IV.

ON INSTINCT.

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nical machines, they might as well whip the sands, halloo to the waves, and whistle to the winds.

Under this view of the subject all instinctive actions were of course referred to a principle of body, or gross tangible matter, not endowed with peculiar or exclusive properties; and wherever any thing of the same description was to be found among mankind, it was instantly separated from all connexion with intelligence, and referred to the same source.

The incongruities accompanying this hypothesis have not, however, prevented other philosophers from following it to a certain latitude in modern times, although it has been seldom, perhaps never of late days, pursued to the extent contended for by Des Cartes. The ideas of Dr. Reid, who has expressly written upon this subject, do not appear to be very perspicuous: yet he obviously espouses the doctrine of a mechanical principle of animal actions; and the actions which are resolvable into this principle are, in his opinion, of two kinds—those of instinct, and those of habit. Instinct is with him, therefore, as well as with Des Cartes, a property of body or gross matter alone, unendowed with any peculiar powers, and merely operated upon by a combination of mechanical forces.

II. In direct opposition to this corporeal hypothesis, Mr. Smellie and Dr. Darwin have contended that instinct is altogether a mental principle, the brute tribes possessing an intelligent faculty of the very same nature as mankind, though more limited in its range. From this point, however, these two physiologists disagree, and fly off in opposite directions: the former contending that reason is the result of instinct,* and the latter that instinct is the result of reason. In the promptitude and perfection with which the newborn infant seeks out and sucks its mother's breast, Dr. Darwin asserts that, although the chain of thought which directs it to the accomplishment of its object is concealed from the view, it still exists; and he endeavours to follow it up and develope it;f in which,however, it is not worth while to accompany him, for the whole process, even upon his own showing, is so complex, that it would rather require the genius of an adult Newton to unfold it, than yield to the dawning powers of a new-born infant.

I will just observe, that in various cases of the instinctive faculty the most excursive theorist cannot picture to his imagination any thing like a chain of thought, or previous reasoning; any thing like habit or imitation, by which the means and the end are joined together. Let us take, as an example, the very common instance of a brood of young ducks brought up under a hen, and contrary to all the instincts and feelings of the foster-mother, plunging suddenly into the water, while she herself trembles piteously on the brink of the pond, not daring to pursue them, and expecting every moment to see them drowned. By what kind of experience or observation, by what train of thought or reasoning has the scarcely fledged brood been able to discern that a web-foot fits them for swimming, and that a fissured foot would render them incapable?—a knowledge that mankind have only acquired by long and repeated contemplation, and which has never been fully explained to this hour.

* Mr. Smellie defines instinct to be "every original quality of mind which produces feelings or actions, when the proper objects are presented to it."—Philos. of Nat. Hist. vol. i. p 155. So, p. 150, "From the above facts and reasonings, it seems to be apparent that instincts are original qualities of mind; that every animal is possessed of some of theae qnalities; that the intelligence and'resources of animals are proportioned to the number of instincts with which their minds are endowed; that all animals are, in some measure, rational beings; and that the dignity and superiority of the human intellect are necessary results, not of the conformation of our bodies, but of the great variety of instincts which nature has been pleased to confer on the species."

In p. 156 be, in like manner, confounds mind with sensation, as he has above confounded instinct « 'I1 mind. "Sensation,*' eayshe, "implies a sentient principle or mind. Whatever fee; s. therefore, is mind. Of course, the lowest species of animals are endowed with mind." It ought to have been first proved that the lowest species of animals are even endowed with sensation.

T " By a due attention to these circumstances, many of the actions, which at first night seemed only referrible to an inexplicable instinct, will appear to have been acquired, like all other animal actions that are attended with consciousness, by the repeated efforts of our muscles under the conduct of our snisitwns or desires.'—Zoonom. Lect. xvi. 2,4. "If it should be asked, what induces a bird to sit weeks on its first eggs, unconscious that a brood of young ones will be the product? the answer must be, that it is the same passion that induces the human mother to hold her offspring whole nights and days in her fond arms, and press it to her bosom, unconscious *-4 'ts future growth to sense and manhood, till observation or tradition have informed her ''—Darwin, Sku • • 13, 4.

Habit, imitation, and instruction would all concur in teaching them to flee from the water, as a source of inevitable destruction: and yet, in opposition to all these influences and premonitions, we see them rush into it, and harmlessly: we see them obeying an irresistible impulse, which directs them to what is fitting, stamped in the interior of their little frames, and which is equally remote from the laws of mind and of mechanism.

In like manner, by what process of imitation, education, or reasoning does the nut-weevil (curculio nucum) seek out exclusively, and with the nicest knowledge of the plant, the green hazel in the month of August, while its nut-shell is yet soft and easily penetrable? What past experience or course of argument instructs her that this is the fruit best adapted, or perhaps only adapted, to the digestive powers of her future progeny? With a finished knowledge of her art, as soon as she is prepared to deposite her eggs, she singles out a nut, pierces it with her proboscis, and then, turning round accurately, drops an egg into the minute perforation; having accomplished which, she passes on, pierces another nut, drops another egg, and so continues till she has exhausted her entire stock. The nut, not essentially injured, continues to grow. The egg is soon hatched; the young larve or maggot finds its food already ripened and in waiting for it; and about the time of its full growth, falls with the mature nut to the ground, and at length creeps out by gnawing a circular hole in the side. It then burrows under the surface of the ground, where it continues dormant for eight months, at the termination of which time it casts its skin, commences a chrysalis of the general shape and appearance of the beetle kind, and in the beginning of August throws off the chrysalid investment, creeps to the surface of the ground, finds itself accommodated with wings, becomes an inhabitant of the air, and instantly pursues the very same train of actions to provide for a new progeny which had been pursued by the parent insect of the year before.

In all such cases it is clear that there is a principle implanted in the living form equally distinct from all mechanical, chemical, and rational powers, which directs the agent by an unerring impulse, or, in other words, impels it by a prescribed and unerring law, to accomplish a definite end by a definite means.

Such instinctive powers are not only allowed upon Mr. Smellie's hypothesis, but are conceived to be almost innumerable; and reason, instead of giving birth to them, is, in his opinion, as I have already observed, the general result of them, and consists in the power of comparing one instinct with another, and assenting to those that preponderate. According to this hypothesis, all the actions of the involuntary organs of the body are so many instincts, as pulsation, digestion, secretion; all natural feelings are so many instincts, as love of life, dread of death, and the desire of progeny; all the passions are so many instincts, as fear, hope, envy, benevolence, reverence, superstition, devotion; and hence life is nothing more than a bundle of instincts ;* and reason, which is itself founded upon an instinctive principle, consists, as I have just observed, of nothing more than a power or tendency to compare the different strengths of these antagonist forces whenever they are brought into a state of action, and to be guided by those that are prepollent; or that offer what is felt or conceived to be the best means of obtaining a proposed end. The objections to which this hypothesis is exposed, or rather the evils chargeable upon it, are innumerable; but it is sufficient to observe, at present, that it as effectually confounds the separate faculties of instinct and reason as the preceding hypothesis of Dr. Darwin, and, consequently, that neither of the two opinions are in any respect more admissible than those which refer the instinctive faculty to a mechanical principle, or, in other words, to the common properties of unorganized matter.

III. There is a third class of philosophers, who, sensible of the difficulty of the case, have endeavoured to get over it by contending that instincts are of a mixed kind: that they either originate in a power which holds an inter

* Transact, of the Royal 8ocietyof Edinb. vol. v. p. 34.

mediate nature between matter and mind; or else are in some instances eimply material, and in others simply mental.

The very excellent and learned Cudworth belonged to the first of these two divisions, and may be regarded as having taken the lead in the scheme which it developes. I have already observed, in a former study, that this profound metaphysician was so strongly attached to the Platonic theory of the creation of the world, that he strove, with the full force of his mighty mind, to restore this theory to general vogue. And as it was one important principle in this theory that incorporeal form, or an active and plastic nature, exists throughout the world independently of pure mind and pure matter, and that the last is solely rendered visible and endowed with manifest properties by a union with this active intermede, Cudworth conceived that all instinctive powers might be satisfactorily resolved into the operation of the same secondary energy in proportion as it pervades the universe.* In opposition to which doctrine, however, it is sufficient to remark, that as the existence of all visible matter, whether organized or unorganized, upon the leading principle of the Platonic theory, is equally the result of this plastic power, and produced by a union with it, it should follow that unorganized matter ought occasionally at least to give proofs of an instinctive faculty, as well as matter in an organized state; proofs of definite means to accomplish a definite end, and that end the general weal, preservation, or reproduction of the body exhibiting it. But as, by the common consent of all mankind, no such faculty is ever to be traced in unorganized matter, it cannot be referred to a principle which is equally common and essential to all visible matter, whether under an organized or an unorganized modification.

At the head of the second division of the last class of philosophers to whom I have referred, we may perhaps place M. Buffon; who, incapable of acceding altogether to the mechanical hypothesis of Des Cartes, yet not choosing to allot to animals below the rank of man the possession of an intelligent principle, kindly endowed them with the property of life, which Des Cartes had morosely withheld by contending that they were mechanical machines alone, and very obligingly allowed them to possess a faculty of distinguishing between pleasure and pain, together with a general desire for the former and a general aversion for the latter. And having thus equipped the different tribes of brutes, he conceived that he had sufficiently accounted for the existence of instinctive actions, by leaving them to the operation of this distinguishing faculty upon the mechanical properties of their respective organs. M. Reimar, however, an ingenious German professor, who flourished towards the close of the last century, did not conceive in the same manner: and hence, in a work immediately directed to the instinct of animals, and published at Hamburgh in 1769, he divides the actions which he apprehends ought to pass under this name into three classes—mechanical, representative, and spontaneous: by the first intending all the proper actions of animal organs over which the will has no control, as the pulsation of the heart, the secretion of the various fluids, and the dilatation of the pupil; by the second, those which depend upon an imperfect kind of memory, and which, so far as it is memory, brutes enjoy in common with mankind; and by the third, those which originate from M. Buffon's admitted faculty of distinguishing pleasure from pain, and the desire consequent upon it of possessing the one and avoiding the other.

It is, however, a sufficient answer to both these opinions, which in truth are founded upon one common basis, that, like the theories of Darwin and Smellie, they equally confound, though in a different manner, powers that are essentially distinct . The founders of these opinions may, with Darwin and Smellie, derive the instinctive faculty from a principle of mind, or with Des Cartes and Dr. Reid from a principle of body; but they have no right to derive it from both, or to contend that its different ramifications originate in some instances from the one source, and in others from the other: though, as

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I have already observed, if they do derive it from mind alone, they will be compelled to admit its existence in a thousand caws in which not a single attribute of mind can be traced; while, if they derive it from body alone, they oiler a cause that is inadequate to the effect produced.

M. Cuvier has taken aground still different from any of these philosophers. He has not, indeed, expressly written upon the subject, but in a very accurate description of a somewhat singular ourang-outang,* he sufficiently unfolds his opinion, that instinct consists of ideas which do not originate from sensation, but flow immediately from the brain, and are truly innate. His words are as follows: "The understanding may have ideas without the aid of the senses; two-thirds of the brute creation are moved by ideas which they do not owe to their sensations, but which flow immediately from their bram. Instinct constitutes this order of phenomena: it is composed of ideas truly innate, in which the senses have never had the smallest share." There is a perplexity in this passage, which I am surprised at in the writings of so exact a physiologist: it first confounds instincts with ideas, as other philosophers have confounded them with feelings; and next affirms that ideas may flow from the brain without the aid of the external senses. That "the understanding may have ideas without the aid of the senses," I admit; but then it cannot have them from the brain, this being the very foundation and fountain of the senses; that from which they rise, and that in which they terminate. The understanding may, undoubtedly, have ideas from the exercise of its own proper powers alone, but this can only be the case with pure intellectual beings, and to assimilate the faculty of instinct with a faculty of this exalted character, is to clothe brutes with endowments superior to those of mankind; it is to elevate the ourang-outang above an Aristotle or a Bacon.

Hence M. Dupont de Nemours, in an article read before the National Institute in 1807, advises to drop the term instinct altogether, as the only means of avoiding the rocks on some of which every writer has shipwrecked himself. He asserts, that there is in fact no such thing in existence; and that every action which has hitherto been described under such name is the mere result of intelligence, of thought, habit, example, or the association of ideas. But this is only to revive, in a new form, the theory of Darwin or of Smellie; while it is only necessary to advert to the explanatory examples offered by M. Dupont himself, to see that many of them are utterly incapable, by any ingenuity whatever, of being resolved into a principle either of intelligence or of mechanism.f

Nothing, therefore, is clearer than that the principle of instinct has hitherto never been explicitly pointed out, nor even the term itself precisely defined: it has been derived from mechanical powers, from mental powers, from both together, and from an imaginary intermediate essence, supposed equally to pervade all imbodied matter, and to give it form and structure. It has been made sometimes to include the sensations, sometimes the passions, sometimes the reason, and sometimes the ideas: it has sometimes been re stricted to animals, and sometimes extended to vegetable life. J

• Annalcs du Museum et d'Hiat. Nat. torn. xvi. p. 46. t Magazine Encyclopedique, Feb. 1307, p. 437.

t Dr. Hancock has lately published a very elaborate volume upon this subject, in which he takes a Just view of tbe instincti t e powers of animals, and is hair-di.sjiosed to allow the same faculty to plants. But 111 merely distinguishing this faculty from reason, in the same way in which he distinguishes what have hitherto be«n called innate principles, a morel sense or faculty, light of nature, divine reason, as contradistinguished from human reason, spiritual power, internal leaching, and even impulse and inspiration of the Holy Spirit, all which he contemplates as intelligences of a like kind, or, to adopt his own words, ••which we can only regard as an Emanation of Divine Wisdom," he has so completed generalized the subject, not to say apparently blended into a common principle powers which have usually been regarded as specifically discrepant from each other,—even allowing the existence of the whole of them, and that they all how, as in such case they must necessarily do, from the same almighty Source of being,—that the peculiar nature of the instinctive faculty is left in as much obscurity asever.

Dr. Hancock has tiodden over an extensive ground of both physical and metaphysical research, and the excellent spirit with which he writes entitles him to the esteem of every good man. Vet I am at a loss to determine why the principle of reason, or the reasoning soul in man, should not have as fair a claim to originate from the divine energy that pervades every part of nature, from the minutest atom to the highest spiritual afllation, as the faculty of instinct. By throwing, however, the principle of human reason out of the generalpslc, and by associating instinct with the high alliances just adverted to, the " unconscious intellifBtue," as Dr. Hancock has denominated it of tbe lowtet part of the animal creation, uvea that of insects

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