It is as if nature had wished, in the mechanical tendencies of animals, to
give the investigator an illustrative commentary upon her works, according
to final causes and the admirable design of her organised productions
which is thereby introduced. For these mechanical tendencies show most
clearly that creatures can work with the greatest decision and
definiteness towards an end which they do not know, nay, of which they
have no idea. Such, for instance, is the bird’s nest, the spider’s web,
the ant‐lion’s pitfall, the ingenious bee‐hive, the marvellous termite
dwelling, &c., at least for those individual animals that carry them out
for the first time; for neither the form of the perfected work nor the use
of it can be known to them. Precisely so, however, does _organising_
nature work; and therefore in the preceding chapter I gave the paradoxical
explanation of the final cause, that it is a motive which acts without
being known. And as in working from mechanical tendency that which is
active is evidently and confessedly the _will_, so is it also really the
will which is active in the working of organising nature.
One might say, the will of animal creatures is set in motion in two
different ways: either by motivation or by instinct; thus from without, or
from within; by an external occasion, or by an internal tendency; the
former is explicable because it lies before us without, the latter is
inexplicable because it is merely internal. But, more closely considered,
the contrast between the two is not so sharp, indeed ultimately it runs
back into a difference of degree. The motive also only acts under the
assumption of an inner tendency, _i.e._, a definite quality of will which
is called its _character_. The motive in each case only gives to this a
definite direction—individualises it for the concrete case. So also
instinct, although a definite tendency of the will, does not act entirely,
like a spring, from within; but it also waits for some external
circumstance necessarily demanded for its action, which at least
determines the time of its manifestation; such is, for the migrating bird,
the season of the year; for the bird that builds its nest, the fact of
pregnancy and the presence of the material for the nest; for the bee it
is, for the beginning of the structure, the basket or the hollow tree, and
for the following work many individually appearing circumstances; for the
spider, it is a well‐adapted corner; for the caterpillar, the suitable
leaf; for egg‐laying insects, the for the most part very specially
determined and often rare place, where the hatched larvæ will at once find
their nourishment, and so on. It follows from this that in works of
mechanical tendency it is primarily the instinct of these animals that is
active, yet subordinated also to their intellect. The instinct gives the
universal, the rule; the intellect the particular, the application, in
that it directs the detail of the execution, in which therefore the work
of these animals clearly adapts itself to the circumstances of the
existing case. According to all this, the difference between instinct and
mere character is to be fixed thus: Instinct is a character which is only
set in motion by a _quite specially determined_ motive, and on this
account the action that proceeds from it is always exactly of the same
kind; while the character which is possessed by every species of animal
and every individual man is certainly a permanent and unalterable quality
of will, which can yet be set in motion by very different motives, and
adapts itself to these; and on account of this the action proceeding from
it may, according to its material quality, be very different, but yet will
always bear the stamp of the same character, and will therefore express
and reveal this; so that for the knowledge of this character the material
quality of the action in which it appears is essentially a matter of
indifference. Accordingly we might explain instinct as a character which
is beyond all measure one‐sided and strictly determined. It follows from
this exposition that being determined by mere motivation presupposes a
certain width of the sphere of knowledge, and consequently a more fully
developed intellect: therefore it is peculiar to the higher animals, quite
pre‐eminently, however, to man; while being determined by instinct only
demands as much intellect as is necessary to apprehend the one quite
specially determined motive, which alone and exclusively becomes the
occasion for the manifestation of the instinct. Therefore it is found in
the case of an exceedingly limited sphere of knowledge, and consequently,
as a rule, and in the highest degree, only in animals of the lower
classes, especially insects. Since, accordingly, the actions of these
animals only require an exceedingly simple and small motivation from
without, the medium of this, thus the intellect or the brain, is very
slightly developed in them, and their outward actions are for the most
part under the same guidance as the inner, follow upon mere stimuli,
physiological functions, thus the ganglion system. This is, then, in their
case excessively developed; their principal nerve‐stem runs under the
belly in the form of two cords, which at every limb of the body form a
ganglion little inferior to the brain in size, and, according to Cuvier,
this nerve‐stem is an analogue not so much of the spinal cord as of the
great sympathetic nerve. According to all this, instinct and action
through mere motivation, stand in a certain antagonism, in consequence of
which the former has its maximum in insects, and the latter in man, and
the actuation of other animals lies between the two in manifold gradations
according as in each the cerebral or the ganglion system is
preponderatingly developed. Just because the instinctive action and the
ingenious contrivances of insects are principally directed from the
ganglion system, if we regard them as proceeding from the brain alone, and
wish to explain them accordingly, we fall into absurdities, because we
then apply a false key. The same circumstance, however, imparts to their
action a remarkable likeness to that of somnambulists, which indeed is
also explained as arising from the fact that, instead of the brain, the
sympathetic nerve has undertaken the conduct of the outward actions also;
insects are accordingly, to a certain extent, natural somnambulists.
Things which we cannot get at directly we must make comprehensible to
ourselves by means of an analogy. What has just been referred to will
accomplish this in a high degree when assisted by the fact that in
Kieser’s “_Tellurismus_” (vol. ii. p. 250) a case is mentioned “in which
the command of the mesmerist to the somnambulist to perform a definite
action in a waking state was carried out by him when he awoke, without
remembering the command.” Thus it was as if he must perform that action
without rightly knowing why. Certainly this has the greatest resemblance
to what goes on in the case of mechanical instincts in insects. The young
spider feels that it must spin its web, although it neither knows nor
understands the aim of it. We are also reminded here of the dæmon of
Socrates, on account of which he had the feeling that he must leave undone
some action expected of him, or lying near him, without knowing why—for
his prophetic dream about it was forgotten. We have in our own day quite
well‐authenticated cases analogous to this; therefore I only briefly call
these to mind. One had taken his passage on a ship, but when it was about
to sail he positively would not go on board without being conscious of a
reason;—the ship went down. Another goes with companions to a powder
magazine; when he has arrived in its vicinity he absolutely will not go
any further, but turns hastily back, seized with anxiety he knows not
why;—the magazine blows up. A third upon the ocean feels moved one night,
without any reason, not to undress, but lays himself on the bed in his
clothes and boots, and even with his spectacles on;—in the night the ship
goes on fire, and he is among the few who save themselves in the boat. All
this depends upon the dull after‐effect of forgotten fatidical dreams, and
gives us the key to an analogous understanding of instinct and mechanical
tendencies.
On the other hand, as has been said, the mechanical tendencies of insects
reflect much light upon the working of the unconscious will in the inner
functions of the organism and in its construction. For without any
difficulty we can see in the ant‐hill or the beehive the picture of an
organism explained and brought to the light of knowledge. In this sense
Burdach says (_Physiologie_, vol. ii. p. 22): “The formation and
depositing of the eggs is the part of the queen‐bee, and the care for the
cultivation of them falls to the workers; thus in the former the ovary,
and in the latter the uterus, is individualised.” In the insect society,
as in the animal organism, the _vita propria_ of each part is subordinated
to the life of the whole, and the care for the whole precedes that for
particular existence; indeed the latter is only conditionally willed, the
former unconditionally; therefore the individuals are even sacrificed
occasionally for the whole, as we allow a limb to be taken off in order to
save the whole body. Thus, for example, if the path is closed by water
against the march of the ants, those in front boldly throw themselves in
until their corpses are heaped up into a dam for those that follow. When
the drones have become useless they are stung to death. Two queens in the
hive are surrounded, and must fight with each other till one of them loses
its life. The ant‐mother bites its own wings off after it has been
impregnated, for they would only be a hindrance to it in the work that is
before it of tending the new family it is about to found under the earth
(Kirby and Spence, vol. i.) As the liver will do nothing more than secrete
gall for the service of the digestion, nay, will only itself exist for
this end—and so with every other part—the working bees also will do
nothing more than collect honey, secrete wax, and make cells for the brood
of the queen; the drones nothing more than impregnate; the queen nothing
but deposit eggs; thus all the parts work only for the maintenance of the
whole which alone is the unconditional end, just like the parts of the
organism. The difference is merely that in the organism the will acts
perfectly blindly in its primary condition; in the insect society, on the
other hand, the thing goes on already in the light of knowledge, to which,
however, a decided co‐operation and individual choice is only left in the
accidents of detail, where it gives assistance and adopts what has to be
carried out to the circumstances. But the insects will the end as a whole
without knowing it; just like organised nature working according to final
causes; even the choice of the means is not as a whole left to their
knowledge, but only the more detailed disposition of them. Just on this
account, however, their action is by no means automatic, which becomes
most distinctly visible if one opposes obstacles to their action. For
example, the caterpillar spins itself in leaves without knowing the end;
but if we destroy the web it skilfully repairs it. Bees adapt their hive
at the first to the existing circumstances, and subsequent misfortunes,
such as intentional destruction, they meet in the way most suitable to the
special case (Kirby and Spence, _Introduc. to Entomol._; Huber, _Des
abeilles_). Such things excite our astonishment, because the apprehension
of the circumstances and the adaptation to these is clearly a matter of
knowledge; while we believe them capable once for all of the most
ingenious preparation for the coming race and the distant future, well
knowing that in this they are not guided by knowledge, for a forethought
of that kind proceeding from knowledge demands an activity of the brain
rising to the level of reason. On the other hand, the intellect even of
the lower animals is sufficient for the modifying and arranging of the
particular case according to the existing or appearing circumstances;
because, guided by instinct, it has only to fill up the gaps which this
leaves. Thus we see ants carry off their larvæ whenever the place is too
damp, and bring them back again when it becomes dry. They do not know the
aim of this, thus are not guided in it by knowledge; but the choice of the
time at which the place is no longer suitable for the larvæ, and also of
the place to which they now bring them, is left to their knowledge. I wish
here also to mention a fact which some one related to me verbally from his
own experience, though I have since found that Burdach quotes it from
Gleditsch. The latter, in order to test the burying‐beetle (_Necrophorus
vespillo_), had tied a dead frog lying upon the ground to a string, the
upper end of which was fastened to a stick stuck obliquely in the ground.
Now after several burying‐beetles had, according to their custom,
undermined the frog, it could not, as they expected, sink into the ground;
after much perplexed running hither and thither they undermined the stick
also. To this assistance rendered to instinct, and that repairing of the
works of mechanical tendency, we find in the organism the _healing power_
of nature analogous, which not only heals wounds, replacing even bone and
nerve substance, but, if through the injury of a vein or nerve branch a
connection is interrupted, opens a new connection by means of enlargement
of other veins or nerves, nay, perhaps even by producing new branches;
which further makes some other part or function take the place of a
diseased part or function; in the case of the loss of an eye sharpens the
other, or in the case of the loss of one of the senses sharpens all the
rest; which even sometimes closes an intestinal wound, in itself fatal, by
the adhesion of the mesentery or the peritoneum; in short, seeks to meet
every injury and every disturbance in the most ingenious manner. If, on
the other hand, the injury is quite incurable, it hastens to expedite
death, and indeed the more so the higher is the species of the organism,
thus the greater its sensibility. Even this has its analogue in the
instinct of insects. The wasps, for instance, who through the whole summer
have with great care and labour fed their larvæ on the produce of their
plundering, but now, in October, see the last generation of them facing
starvation, sting them to death (Kirby and Spence, vol. i. p. 374). Nay,
still more curious and special analogies may be found; for example, this:
if the female humble‐bee (_Apis terrestris, bombylius_) lays eggs, the
working humble‐bees are seized with a desire to devour them, which lasts
from six to eight hours and is satisfied unless the mother keeps them off
and carefully guards the eggs. But after this time the working humble‐bees
show absolutely no inclination to eat the eggs even when offered to them;
on the contrary, they now become the zealous tenders and nourishers of the
larvæ now being hatched out. This may without violence be taken as an
analogue of children’s complaints, especially teething, in which it is
just the future nourishers of the organism making an attack upon it which
so often costs it its life. The consideration of all these analogies
between organised life and the instinct, together with the mechanical
tendencies of the lower animals, serves ever more to confirm the
conviction that the _will_ is the basis of the one as of the other, for it
shows here also the subordinate rôle of knowledge in the action of the
will, sometimes more, sometimes less, confined, and sometimes wanting
altogether.
But in yet another respect instincts and the animal organisation
reciprocally illustrate each other: through the _anticipation of the
future_ which appears in both. By means of instincts and mechanical
tendencies animals care for the satisfaction of wants which they do not
yet feel, nay, not only for their own wants, but even for those of the
future brood. Thus they work for an end which is as yet unknown to them.
This goes so far, as I have illustrated by the example of the Bombex in
“The Will in Nature” (second edit. p. 45, third edit. p. 47), that they
pursue and kill in advance the enemies of their future eggs. In the same
way we see the future wants of an animal, its prospective ends,
anticipated in its whole corporisation by the organised implements for
their attainment and satisfaction; from which, then, proceeds that perfect
adaptation of the structure of every animal to its manner of life, that
equipment of it with the needful weapons to attack its prey and to ward
off its enemies, and that calculation of its whole form with reference to
the element and the surroundings in which it has to appear as a pursuer,
which I have fully described in my work on the will in nature under the
rubric “Comparative Anatomy.” All these anticipations, both in the
instinct and in the organisation of animals, we might bring under the
conception of a knowledge _a priori_, if _knowledge_ lay at their
foundation at all. But this is, as we have shown, not the case. Their
source lies deeper than the sphere of knowledge, in the will as the thing
in itself, which as such remains free even from the _forms_ of knowledge;
therefore with reference to it time has no significance, consequently the
future lies as near it as the present.