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tions, unless we arrive at some stead- term which we are called upon seri. fast conclusions upon this subject of ously to investigate, is that which instinct. It is a stumbling-block that opposes instinct to reason as some must be removed from our path. It peculiar mode of thought. Speaking lies there, a mysterious something be- of the human understanding, we all tween sensation and thought. We acknowledge that ideas of individual say that there cannot be, in any in- objects are derived only through the telligible sense of the word, a special senses; we all acknowledge that to cerebral organ for an instinct; be- act from a purpose, to use means to cause, according to our definition, an an end, implies an exercise of meinstinct is that sympathy or harmony mory. Now, every animal has some (an instance of that harmony which mode of taking its prey, or of framing runs through all nature) established a shelter or nest for itself, in which directly between nerve and nerve, and it is quite perfect, without any teachlimb and limb. What is more than ing or experience whatever. It acts this is thought, and falls under our as if from design, and yet what we great organ of memory.
understand as thought or design could Human actions have become so not have been present. Are we to say complicated with human thought, that that there is here manifested some by general consent we appeal to the quite different mode of thinking, or of lower animals when we would discuss ideation, than that which men are the nature of instinct. To them, cognisant of ? Or, recognising the therefore, we must turn for a mo fact that all the phenomena of nature ment.
must wear this aspect of design, shall There is, perhaps, no word in the we not place the design here also at language which has been used so va once and only in the great Author of riously and vaguely as this of instinct. nature, and seek to explain the pheSometimes we hear it employed to nomena before us by such causes as designate all the actions of the lower we know to exist-by sensational imanimals; and those which are most pulses or irritability, combined with plainly indicative of thought or me- such faculty of perception and memory mory are singled out as remarkable as the animal may have in common instances of instinct. At other times with man? That a measure of what it is even employed to designate some we call judgment and intelligence lies of the higbest attributes of the human in the very nature of perception, and mind, and anything is called instinc- memory itself, we have already intitive which wears a primary charac- mated. ter, and refers us to no known cause. It is this last view wbich bas forced The author before us slides into this itself upon our convictions, though lax use of the term in the following we are afraid we shall not be able to passage : “Still it seems to me that do justice to it in our present limits. to reason well is the result of an in. We object entirely to the introduction stinct originally implanted in us, rather of an instinctive mode of thought. than of instruction; and that a child That through their organs of sense or a peasant reasons quite as accur- animals have sensations different from ately on the thing before him and within ours, is past dispute. There is no octhe sphere of his knowledge, as those casion to introduce this other startwho are versed in all the rules of ling anomaly of a thinking which orilogic."* But the only use of the ginates in a quite different manner.
* An appeal to instinct is brought in, curiously enough, in one place, to solve an old ethical controversy : “ The desire to live in society is as much an instinct in him (man) as it is in the bee, or the ant, or the beaver, or the prairie dog. Ought not this to settle the disputed question as to the existence of a moral sense ?" Yes; either party in the controversy would answer-50 far as your moral sense is that of the bee, or the beaver, or the prairie dog.
So far from being surprised that animals should live in society, one is rather perplexed that any should live solitary. Even the sense of contact is agreeable ; and the mutual caress given and received, in some form or other, is a bond of union. It is their mode of obtaining subsistence, we presume, that enforces solitude on some animals.
Through the olfactory nerves alone there is in animals (and of course in what a variety of sensations is evi. man) any peculiar mode of thinking to dently diffused through the various be called instinct. We oppose instinct quadrupeds, and fishes, and birds, to reason not because it is some difwhich people the earth, the sea, and ferent mode of thought, but because the air! Nor can any one for a mo- it is a mode of action in which thought ment have reflected upon the laws of does not occur. It is developed prior animal life without noticing the direct to the development of memory. connection established between sensa- We are aware that the popular imtions, or rather those irritabilities and pression is here against us, and contractilities which accompany sen- that a sort of intuitive knowledge is sation, and the motions of the variously ascribed very liberally to the animal constructed limbs. A peculiar scent kingdom. We must admit also that at once calls into play those internal this popular impression has been sensations we describe as hunger or supported by great names, and great appetite; and these again throw every authorities. Cuvier has expressed the limb into motion, as well those that opinion that the lower animals are capture the prey as those that devour "moved by ideas which they do not it. Nor is it through the scent alone owe to their sensations, but which that the animal is roused into activity; flow immediately from the brain." that the sight also and the hearing Such an hypothesis contradicts all we communicate peculiar nervous tre- do know of the nature of that thought mours to different animals is equally which represents external objects to certain. What else can be that anti- us; and we may safely say, therefore, pathy which the mere sight of one that it is not to be received till other animal immediately excites in an- modes of explanation in harmony other, leading in one case to hostile with that knowledge have been tried. movement, and in another to flight? Some writers, struck with the singular A complete series of actions is pro fact that habits acquired by one duced, in which the relation of means generation of animals become heredito an end is indeed most conspi- tary instincts in subsequent generacuous, without the intervention, how- tions, have concluded that this could ever, of thought on the part of the be explained only by the supposition animal.
that some modified form of the brain We repeat, in order to avoid mis had been inherited. But the fact is take, that we do not dispute the pos- by no means established that the effect session of memory in any case where of a habit (as that of the pointer dog) there is fair ground for presuming its is to modify exclusively the brain. existence; and in memory itself, there There is much in the subject of habit is involved a certain measure of that that is very obscure. This, at all species of intelligence, which uses events, is quite clear, that the transmeans to an end. It may happen, formation of a habit into an instinct, that in some of the lower animals is only one branch of the still larger memory, acting in a very narrow subject-What is the law by which circle on a few objects of urgent the instincts of a race of animals are want, may display singular vigour modified ? That they do admit of and tenacity. Neither do we think change is certain, old ones decaying that comparative anatomy authorises from non-exercise, and new ones beus to conclude that, where a cerebrum ing introduced. is not developed, memory cannot ex. We shall obtain no support to our ist; because comparative anatomy it- opinions from the author before us. self teaches us, that a function which, Sir Benjamin Brodie makes many in its higher stage of development, observations upon instinct with which has a special organ, may, in a lower we entirely concur; but in the passage stage, be combined with other functions where he approaches nearest to a dein a common tissue. The ganglion finition of the term, he couples it with, which occupies the head of an insect "voluntary exercise of the muscles," may perform the function which in the and speaks of it habitually as a species vertebrate animal devolves upon the of knowledge: there is much, however, cerebrum. What we dispute is, that in the following quotation for which
we very willingly avail onrself of his of any form of thought, or any cerebral authority.
function. By so doing the mind fa“ Food is required because life cannot miliarises itself with the truth, that a be maintained without it. But no one large portion of animal life is complete under ordinary circumstances thinks of in itself, independently of the develop this ultimate object. We have an uneasy ment of memory. sensation which we call hunger, and it is We will take up Mr Rymer Jones's merely to remove this sensation that we book on the Animal Kingdom.* It are led to eat. This is the simplest form of
will supply us with the facts we are in instinct, and it goes far towards explain
want of; and it will also supply us with ing others which are more complicated.
a striking illustration of the very The desire for food is the same in the newly-born child as in the grown-up man ;
tendency of the imagination we have and, when applied to his mother's breast,
to contend against. For we shall seo he honows at once how to obtain it by
that even a Professor of Zoology canbringing several pairs of muscles of his not look upon the lowest forms of mouth and throat successively into action, animated nature without investing making the process of suction. The new them with human feelings, and human ly-born calf knows at once how to bal powers-with faculties of the human ance himself on his four legs, to walk and being which he would no doubt reclaim seek the food with which he is supplied from them the moment his attention by his mother. The duckling hatched by was seriously drawn to the subject. the hen, as soon as his muscular powers are sufficiently developed, is impelled by
There is no fact in physiology more
certain than that irritability or conthe desire to enter the neighbouring pond, and when in the water, without example
tractility exists prior to, or indepenor instruction, he calls certain muscles dent of sensation. The series of into action, and is enabled to swim. movements which a decapitated frog When a sow is delivered of a litter, each will perform on the application of very young pig, as it is born, runs at once to ordinary stimulants ; those movetake possession of one of his mother's ments in the human frame, which nipples, which he considers as his peculiar take place without any accompanying property ever afterwards."
sensation, and which are ranged unMany probably would be ready to der the title of reflex action,-a host of admit that the peculiar impulse which experiments and observations establed the duckling into the water, and lish beyond a doubt, that both where the movement of its limbs in that there is, and where there is not, a element, might be explained without visible nervous system, complex and supposing any knowledge on the part harmonious actions are performed on of the animal-might be resolved into the mere basis of irritability or conmere vital phenomena as distin- tractility. The simplest order in the guished from psychical. But when animal kingdom, here called the Acrita, a more complex series of actions is are manifestly endowed with no higher performed, when some peculiar in- vital property than this,—we meet genuity, as it appears, is displayed in with no one who seriously believes capturing prey, or building a nest, that they are sensitive. The sponge they cannot refrain from the conclu- is the first of these Acrita which Mr sion that actions so like those which Jones describes ; he finds in it no would be produced by human thought, trace whatever of sensation, no signs really had their origin in some species that it feels, no organisation such as of thought. We know no way of suc- we are accustomed to consider necescessfully combating this tendency of sary to sensation. But in the body the imagination, except that of direct of the old sponges grow certain ing the attention to those lower forms "yellowish gelatinous granules" or of animal life, where there is a con- " gemules," destined to be future siderable complexity of action, and sponges. Now, mark how soon the where there is absolutely no ground imagination seizes upon our writer, whatever for supposing the existence in his description of these youthful
* A General Outline of the Animal Kingdom, and Manual of Comparative Anatomy. By Thomas RYMER JONES, F.L.S., Professor of Comparative Anatomy in King's College, London.
sponges - mark it, not by way of them. Mr Jones cannot describe criticism of Mr Jones, but as an in- their movements without inferring cerstance of the almost irrepressible tain mental and even moral qualities. tendency of the imagination to invest The hydra“ selects" its position, it animal movements with the psychical is “ watching for its prey," it " waits properties of man.
patiently." When “gorged with prey,
or when indisposed to take food, al“ The gemule assumes an ovoid form, thonch other animals may tonch' the and a large portion of its surface becomes covered with innumerable vibrating hairs
tentacula again and again, they escape or cilia, as they are denominated, which
with impunity." And yet all that we are of inconceivable minuteness, yet in
have really before us is a creature dividually capable of exercising rapid framed to supply itself with food ; at movements which produce currents in the the approach of the appropriate food surrounding fluid. Instead, therefore, of the tentacula are stimulated, contract falling to the bottom of the water, the or coil themselves up, and draw it into ceaseless vibration of the cilia propels it the stomach. Note especially the rapidly along until, being removed a con- harmony between wants of the sto. siderable distance," (it attaches itself to
mach and the susceptibility of these some object, loses the locomotive cilia,
tentacula; when the stomach is in a and becomes an ordinary sponge). “The
state of repletion their irritability and seeds of vegetables, sometimes winged and plumed for the purpose, are blown about
movement cease. by the winds, and transported by various
Let us proceed to a class of animals agencies to distant places, but, in the
where traces of a nervous system bepresent instance, the still waters in which come evident, and some slight sensasponges grow would not have served to tion may be supposed to accompany transport their progeny elsewhere. In their movements, but where there is stead, therefore, of being helpless at their no brain whatever, "Let any of our birth, the young sponges can by means of readers," says Mr Jones, “ pick up their cilia row ihemselves about at pleasure, from the beach one of these animals, and enjoy for a period powers of locomotion
the common star-fish of our coast, denied to their adult state."
which, as it lies upon the sand left by Row themselves about at pleasure the retiring waves, appears so incaEnjoy for a period! Both sensation pable of movement, so utterly helpand volition are supplied to this ani- less and inanimate; let him place it mal seed, furnished with a plume which in a large glass jar filled with its nathe stimulant of the water keeps in tive element, and watch the admirits vital movement. These minute able spectacle which it then presents. cilia the microscope has detected in Slowly he perceives its rays expand to the tissues of the human body, where their full stretch, hundreds of feet are certainly there is no consciousness of gradually protruded through the amtheir automatic movements. Nor bulacral apertures, and each, apparwould Mr Jones, if the question were ently possessed of independent action, seriously put to him, countenance the fixes itself to the sides of the vessel az idea that they were sensitive.
the animal begins its march. The We pass to the well-known polyp, numerous suckers are soon all emthe Ilydra—that " animal plant," as ployed fixing and detaching themsome have called it-an organic struc- .selves alternately, some remaining ture endowed with irritability which firmly adherent, while others change is excited by the presence of water, or their position ; and thus, by an equable light, or contact with any solid sub- gliding movement, the star-fish climbs stance. Mr Jones endows such ani- the sides of the glass in which it is mals with a fine sense of touch. Ac- confined, or the perpendicular surface cording to all analogy, such a fine of the submarine rock.' sense of touch must subject them to The nervous apparatus of this aniexquisite pain when rudely struck, mal is extremely simple, consisting of and yet no means of escape from dan- a circular cord round its mouth, from ger has been afforded them. But which are given off two delicate filatheir tentacula move as if they had ments to each ray. Some have dethe sense of touch, and the imagina tected a third filament running to the tion can hardly help supplying it to locomotive suckers. Mr Jones, for what reason we do not gather, is not tainly the stupid carp, as he is here disposed to regard these nerves as not very fairly called, does manifest seats of sensation, but merely “ as some memory, but probably in many serving to associate the movements instances his sensations never become performed by the various parts of the thoughts, and in all these cases they animal.” The irritable skin he re- exist as final ends—80 much pleasure gards as the principal agent in initiat- to the animal, nothing more. And ing its movements. In this last opin- take the case of the winged insect, the ion he is no doubt perfectly correct, moth that again and again flies into but it does not follow that these nerves the flame of your candle till it has demay not also be the seats of certain stroyed itself-here there is little or sensations of pleasure or of pain no memory manifested. But you chiefly, let us hope, of pleasure. We would not say that the animal is shall take it for granted that there is without sensation. The whole prosome vague sensation in these nerves, ceedings of such an insect appear to knotted as they are by their diminutive us to be carried on by the mere laws ganglion to the circular cord.
of vital action ; what it has of sensaBut what we wish to bring before tion is so much of pleasure; it never the attention of our reader is this : becomes guidance or knowledge. Here is an animal moving its five “Every limb," says Unzer, a Gerrays and its hundred feet in perfect man physiologist, who wrote some harmony, climbing up the rocks and time ago, but who had paid great atseizing its prey. It has no eye, no tention to this subject of instinctear, no scent; it is described as a "every limb has its own appetite of mere“ walking stomach." Whether action,"-wbich again is in perfect it has or has not some sensation of harmony with all other limbs and ortouch felt in those slender nerves, gans of the body. Whether the phrase there is no one, at least, who would be altogether admissible or not, it exdream of assigning to it any thought presses very vividly what we conwhatever, whether of the instinctive stantly see in the animal creation. or human kind. There is no cerebral The sight or scent of its destined prey organ of instinct here, and yet we excites the rage of hunger,-claw and have seen how admirably this crea- beak, talons and the jaw, fulfil their ture progresses, and know very well functions; some creature is destroyed that it gets abundantly fed. Here, at and devoured. How utterly idle and least, what we call instinct must be misplaced does it appear to us to talk shared amongst all the limbs of the here of an organ of destructiveness," creature can be described as nothing or an instinct of destructiveness. What but a humble instance of that har- is the result of many harmonious immony wbich runs throughout creation. pulses and feelings is converted into a
And here let us make a remark pre-existing purpose, an idea which is which appears by many to be quite in to flow at once from the brain," as overlooked. To the animal who has it could not possibly enter by the no thought, sensation is not a means channel of the senses. to any further end in the economy of There is a beautiful illustration of the animal ; it is the end itself of its these vital powers bursting at once existence. The sensation manifests into harmonious action, which is the presence of that irritability which not unfrequently quoted. Sir Joseph is the real motor power, but where Banks and his friends, when travelit does not give rise to thought or ling in some tropical country, observed memory, the sensation, as sensation, an alligator's egg lying in the sand, does nothing in directing the animal. under the burning sun. He broke the “We cannot suppose," says Sir Ben- egg, and forth sped the young allijamin Brodie, “the existence of mere gator. Its eye caught sight of the sensation without supposing that there river, and every Jimb basted towards is something more. In the stupid it. Sir Joseph interposed his stick ; carp, which comes to a certain spot the stick was bit at, and all the signs at a certain hour, or on a certain sig- of anger immediately manifested. nal, to be fed, we recognise at any Now, what is this appetite for the river rate the existence of memory." Cer- but some sensation which (as in the