There is not, within the wide range of philosophical inquiry, a subject more intensely interesting to all who thirst for knowledge, than the precise nature of that important mental superiority which elevates the human being above the brute, and enables man alone to assume the sway wheresoever he plants his dwelling; and to induce changes in the constitution and adaptions of other species, which have no parallel where his interference is unknown.

I am led to offer a few remarks on this subject, by observing continually that the instinctive actions and resource of animals are attributed, most inconsiderately, to the habitual exercise of their reflective faculties; often where it is utterly and manifestly impossible for them to have observed facts whereon to base those inferences, which alone could have led them, by an inductive process, to adopt the course we find them to pursue.  I am perfectly aware that the word "instinct," by not a few, is denounced as a mere cloak for ignorance, as a sort of loophole through which to escape from a rational explanation of phenomena; but, with all deference to those who advocate this over and above refined notion, I venture to maintain that it has a very definite signification, to express which no other term could be substituted: it implies an innate knowledge, which is not, like human wisdom, derived exclusively from observation and reflection, and to assign a secondary cause for which is clearly impossible; wherefore it savours rather, I conclude, of sophistry, to affect to be dissatisfied with any non-misleading expression, which is currently understood to denote it.

Place a juvenile chimpanzee in presence of one of its natural enemies; a python, or one of the larger Feles; and it "instinctively" recoils with dread.  But does a human infant evince the like recognition?  Here, then, is a fundamental distinction at the outset.

Not only, too, do brute animals (as remarked by White of Selborne) attempt, in their own defence, to use their natural weapons before these are developed, but they intuitively understand the mode of warfare resorted to by their brute opponents.
   They know , also, where the latter are most vulnerable, and like wise where their concealed weapons lie. Observe the deportment of a rat that is turned into a room with a ferret: see how artfully he guards his neck against the wall, instinctively knowing that there only will his enemy fix.^l  Notice, on the other hand, the wondrous accuracy with which the Mustelidae constantly wound the jugular vein of any bird or quadruped they attack.  Witness a thrush that has captured a wasp, first squeezing out the venom from its abdomen, before it will swallow it.  Or see a spider trying to shake off a wasp from its web, and, failing to do so, proceeding to cut it clean away.  Can aught analogous be traced in the actions of inexperienced man?  Whence, then, the acquired knowledge on which these animals could reason to act thus?

The distinction is, that, whereas the human race is compelled to derive the whole of its information through the medium of the senses, the brute is, on the contrary, supplied with an innate knowledge of whatever properties belong to all the natural objects around, which can in anywise affect its own interests or welfare; a sort of intimation, by the way, that all the inferior races pertain to some general comprehensive system, all the components of which have a mutual reciprocal bearing, and to which man only does not intuitively conform nor constitute a part of, except in so far as his bodily frame is of necessity subject to the common laws of matter and of organisation.²

In every other species, each individual comes into the world replete with "instincts," which require no education for their development.  A kitten reared by hand, or a bird raised from the nest, have the same language, the same leading habits, as the rest of their species, but little, if at all, modified by change of circumstances.³  A kitten watches at a mouse-hole, though it has never seen a mouse; the squirrel proceeds by the easiest possible method to get at the kernel of its first nut, by invariably scraping, with its lower incisors, at the softer end, which it instinctively turns in its fore paws to the proper position; and the wasp, crawling forth from its pupa envelope, immediately commences feeding the neighbouring larvae.
The human infant, too, applies instinctively to the breast, like the young of all other mammalians; but, unlike those, it has to attain all its after-knowledge through the medium of its external senses.  It looks to its nurses, and those about it, for information; and these are capable of so communicating their attainments, as very materially to assist the infant learner in its acquisition of knowledge.  It is preposterous to assert the contrary, as has been done; or to pretend that it rests on the choice of the infant whether or not it will learn.
Practically, it cannot help doing so; and it is equally monstrous to deny that human beings can so communicate the results of their experience, that, with what in addition is ever accumulating, each generation must necessarily rise in knowledge above the last.  Unless the faculties were to be much deteriorated, it could not be otherwise.  Who can pretend to deny the excessive influence of every generation upon that which immediately succeeds it; the influence both of precept and example?  Imagine it possible for those of the present day to refuse to instruct; and what would then be the consequent condition of their offspring?  Apply the same test to any other species of animal; and in what measure would the progeny be affected?

I wish not to defend the untenable doctrine, that the higher groups of animals do not individually profit by experience; nor to deny to them the capability of observation and reflection, whereby to modify, to a considerable extent, their instinctive conduct: neither do I assert that the human race is totally devoid of intuition, when I see the infant take naturally to the breast; when I perceive the force of the maternal attachment, and the ardour of the several passions: which latter, however, are, of course, but incentives to conduct common to both man and animals.  In only the human species are the actions resulting from them unguided by intuitive knowledge.  All I contend for is, that the ruling principle of human actions is essentially distinct from that which mainly actuates the brute creation, whence the general influence of the two is diverse in kind; and I mistake if I cannot establish the position.

The brief period that elapses before most animals are compelled to perform the part allotted to their species, precludes the possibility of their attaining sufficient information from external sources, and renders, therefore, the possession of a substitute for knowledge so obtained absolutely requisite.  We have already seen that such a substitute is not wanting; but that all the knowledge necessary to insure their general welfare is intuitively conferred on the brute creation.
Their various actions, in wild nature, are consequently based on this innate knowledge; which, being the same in every individual of the same species, in a natural state (that is, as completely uncontrolled by those peculiar changes of condition which man only, the exception of all other animals, can bring about), superinduces a normal uniformity of habit throughout the members of a species, which is rarely modified to any considerable extent by individual experience.
Now, this uniformity is at variance with what reasoning from observation could possibly lead to; and, as it extends even to the resource of creatures of the same species, when driven to emergency, we have herein sufficient intimation that their wiles and stratagems, however consonant with what reasoning from observation might suggest, may nevertheless be purely instinctive, perfectly unalloyed with any wisdom resulting from experience.

To ascend from illustrations the least equivocal, let me here cite the nidification of the feathered tribes.  Who, that considers the wonderful fact, that not only genera, but even species, of birds are for the most part distinctly indicated by their nests, can fail to recognise in this the operation of a principle essentially distinct from that which we understand by the word reason? which latter, in human beings, can of course, be only the result of observation and reflection.⁴
We observe a similar marked uniformity in the fabrics and operations of all animals of identical species (man only exempted), endless examples of which will instantly recur to the reader in the insect tribes; and, if we consider the beaver, and others of the higher grades of animals which join their labours for mutual advantage, or are otherwise remarkable for what has thoughtlessly been deemed their ingenuity, the same truth will be found still to hold just as obviously apparent, and forbids us to attribute their proceedings to aught else than the dictates of intuition.

It is most commonly, however, in the resource of brute creatures, the wisdom they display in their expedients, that unreflecting persons fancy they discern the proofs of intellect identical with human; but, even here, this does not necessarily follow; for it is sufficient to refer to the cases which I commenced by detailing, to be assured that Providence has conferred instinctive wiles on animals as a resource against contingencies; the legitimate actions resulting from which according, perhaps, with what reason might dictate in like circumstances, we are therefore apt to conclude must necessarily have been induced by reasoning.  To illustrate what I mean, let me adduce the simulation of death practised by so many species, with intent to weaken the instinctive vigilance of their foes or prey.  (That another animal, it may be remarked, should suffer itself to be thus duped, is most probably a result of acquired experience.)
A cat has been seen to feign death, stretched on a grassplot, over which swallows were noticed sailing to and fro; and by this ruse to succeed in capturing one which heedlessly approached too near it.  The fox has been known to personate a defunct carcass, when surprised in a henhouse; and it has even suffered itself to be carried out by the brush, and thrown on a dungheap, whereupon it instantly rose and took to its heels, to the astounding dismay of its human dupe.  In like manner, this animal has submitted to be carried for more than a mile, swung over the shoulder, with its head hanging; till at length, probably getting a little weary of so uncomfortable a position, or perhaps reasoning that its instinctive stratagem had failed in its object, it has very speedily effected its release, by suddenly biting.
The same animal has been known, when hunted, to crouch exposed upon a rock of nearly its own colour, in the midst of a river, and so to evade detection by its pursuers; and we perpetually hear such cases brought forward as decisive proofs of its extreme sagacity.  However, as regards the latter instance, will not a brood of newly hatched partridges instantly cower and squat motionless at sight of a foe?⁵ and, as concerns the former, do we not find that many beetles, though just emerged from the pupa state, will simulate death every bit as cleverly as a fox or corncrake?  Whence it surely follows that there can be no occasion to attribute the act to a reasoning process in the one animal, any more than in the other.

It would be unnecessary to enter here into any details on the obvious correlativeness of the dominant instincts of animals to the mode of life most congenial to their constitution, to remark on the mutual relations of habit and structure, and the exquisite adaptation of structure to locality.  Hence, the natural habits of species of necessity bear reference to their indigenous haunts, as manifestly as their structural conformation.  Thus, the elephant, which, like the other great Pachydermata, affects the vicinity of rivers and marshes, delights to relax its rigid hide in the stream; and afterwards covers it with a thick plastering of mud, probably to retard its too rapid desiccation: the which has been deemed an incontrovertible proof of its reasoning from observation.
A young robin, however, the first time that it sees water, will, if it be not too deep, fearlessly plunge in and wash; and a young wren or lark will avail itself of the earliest opportunity to dust its feathers on the ground, the exact purport of which is not yet definitely understood.  If, therefore, the latter be thus obviously instinctive, what reason have we to esteem the former otherwise?  The uniformity of all these habits and propensities, in creatures of the same species, tends rather to intimate that in neither case are they the result of reasoning.

To infer reflection on the part of brutes, as many have not scrupled to do, as the motive for whatever in human actions could only be the result of reasoning, one would imagine to be too palpable a misapprehension to need serious consideration; yet some writers have gone so far as to attribute forethought to the dormouse, and other species which provide instinctively against the winter season.
Perhaps it might be deemed a sufficient overthrow to this most shallow notion, to call in mind the migrative impulse; to inquire how the untaught cuckoo (raised by permanently resident foster parents) could reason that in another clime it should escape the rigors of a season that it had never experienced?  But herein we have an additional principle involved, which will require a separate consideration.
Proceed we, then, to examine into the presumed sagacity of those provident creatures, as the ant and harvest mouse, that habitually lay up a store for future need, and even provide against all possible injury from germination, by carefully nibbling out the corcule from each grain.
Can any thing be more truly wonderful as a matter of instinct?  All instincts are, indeed, equally wonderful.  But it would certainly be even more extraordinary, if every member of these species were to be alike induced to pursue the same course by a process of reasoning.  The following anecdotes will suffice to probe the intellect of these animals.

I have a tame squirrel, which, though regularly fed all its life from day to day, nevertheless displays the intuitive habit of its race, in always hoarding the superfluities of its food.  Now, in its mode of effecting this, a superficial observer might fancy that he discerned a fair share of intelligence.  Carrying a nut, for instance, in its mouth, it scrapes a hole with its fore paws in the litter at the bottom of its cage; and then, after depositing its burthen, scratches together the hay, or whatever it may be, over it, and pats it down with its paws.  Moreover, it never fails to remember the spot, and will occasionally, when not wishing for food, examine the place to ascertain whether it be safe.
But mark the sequel. I have repeatedly seen the same animal act precisely thus on the bare carpet, and upon a smooth mahogany table; yes, upon a table I have frequently seen it deposit its nut, give it a few quick pats down, and finally thus leave it wholly unconcealed.⁶  The tits (Pari), also, evince a like propensity of hiding food, one of their many resemblances to the Corvidae; and a tame marsh tit that I once possessed used habitually to drop the remainder of the almond, or piece of suet, that he had been picking, into the water-glass attached to the cage, although he never could thence reobtain it, and though his water was thus daily rendered turbid. I could narrate analogous instances without number.