Chapter III — GENERAL PRINCIPLES OF EXPRESSION—concluded

The principle of direct action of the excited nervous system on the body,
independently of the will and in part of habit—Change of colour in
the hair—Trembling of the muscles—Modified secretions—Perspiration—Expression
of extreme pain—Of rage, great joy, and terror—Contrast
between the emotions which cause and do not cause expressive movements—Exciting
and depressing states of the mind—Summary.

We now come to our third Principle, namely, that certain actions which we
recognize as expressive of certain states of the mind, are the direct
result of the constitution of the nervous system, and have been from the
first independent of the will, and, to a large extent, of habit. When the
sensorium is strongly excited nerve-force is generated in excess, and is
transmitted in certain directions, dependent on the connection of the
nerve-cells, and, as far as the muscular system is concerned, on the
nature of the movements which have been habitually practised. Or the
supply of nerve-force may, as it appears, be interrupted. Of course every
movement which we make is determined by the constitution of the nervous
system; but actions performed in obedience to the will, or through habit,
or through the principle of antithesis, are here as far as possible
excluded. Our present subject is very obscure, but, from its importance,
must be discussed at some little length; and it is always advisable to
perceive clearly our ignorance.

The most striking case, though a rare and abnormal one, which can be
adduced of the direct influence of the nervous system, when strongly
affected, on the body, is the loss of colour in the hair, which has
occasionally been observed after extreme terror or grief. One authentic
instance has been recorded, in the case of a man brought out for execution
in India, in which the change of colour was so rapid that it was
perceptible to the eye.[301]

Another good case is that of the trembling of the muscles, which is common
to man and to many, or most, of the lower animals. Trembling is of no
service, often of much disservice, and cannot have been at first acquired
through the will, and then rendered habitual in association with any
emotion. I am assured by an eminent authority that young children do not
tremble, but go into convulsions under the circumstances which would
induce excessive trembling in adults. Trembling is excited in different
individuals in very different degrees and by the most diversified causes,—by
cold to the surface, before fever-fits, although the temperature of the
body is then above the normal standard; in blood-poisoning, delirium
tremens, and other diseases; by general failure of power in old age; by
exhaustion after excessive fatigue; locally from severe injuries, such as
burns; and, in an especial manner, by the passage of a catheter. Of all
emotions, fear notoriously is the most apt to induce trembling; but so do
occasionally great anger and joy. I remember once seeing a boy who had
just shot his first snipe on the wing, and his hands trembled to such a
degree from delight, that he could not for some time reload his gun; and I
have heard of an exactly similar case with an Australian savage, to whom a
gun had been lent. Fine music, from the vague emotions thus excited,
causes a shiver to run down the backs of some persons. There seems to be
very little in common in the above several physical causes and emotions to
account for trembling; and Sir J. Paget, to whom I am indebted for several
of the above statements, informs me that the subject is a very obscure
one. As trembling is sometimes caused by rage, long before exhaustion can
have set in, and as it sometimes accompanies great joy, it would appear
that any strong excitement of the nervous system interrupts the steady
flow of nerve-force to the muscles.[302]

The manner in which the secretions of the alimentary canal and of certain
glands—as the liver, kidneys, or mammæ are affected by strong
emotions, is another excellent instance of the direct action of the
sensorium on these organs, independently of the will or of any serviceable
associated habit. There is the greatest difference in different persons in
the parts which are thus affected, and in the degree of their affection.

The heart, which goes on uninterruptedly beating night and day in so wonderful
a manner, is extremely sensitive to external stimulants. The great
physiologist, Claude Bernard,[303] has shown how the least excitement of a
sensitive nerve reacts on the heart; even when a nerve is touched so slightly
that no pain can possibly be felt by the animal under experiment. Hence when
the mind is strongly excited, we might expect that it would instantly affect in
a direct manner the heart; and this is universally acknowledged and felt to be
the case. Claude Bernard also repeatedly insists, and this deserves especial
notice, that when the heart is affected it reacts on the brain; and the state
of the brain again reacts through the pneumo-gastric nerve on the heart; so
that under any excitement there will be much mutual action and reaction between
these, the two most important organs of the body.

The vaso-motor system, which regulates the diameter of the small arteries,
is directly acted on by the sensorium, as we see when a man blushes from
shame; but in this latter case the checked transmission of nerve-force to
the vessels of the face can, I think, be partly explained in a curious
manner through habit. We shall also be able to throw some light, though
very little, on the involuntary erection of the hair under the emotions of
terror and rage. The secretion of tears depends, no doubt, on the
connection of certain nerve-cells; but here again we can trace some few of
the steps by which the flow of nerve-force through the requisite channels
has become habitual under certain emotions.

A brief consideration of the outward signs of some of the stronger
sensations and emotions will best serve to show us, although vaguely, in
how complex a manner the principle under consideration of the direct
action of the excited nervous system of the body, is combined with the
principle of habitually associated, serviceable movements.

When animals suffer from an agony of pain, they generally writhe about
with frightful contortions; and those which habitually use their voices
utter piercing cries or groans. Almost every muscle of the body is brought
into strong action. With man the mouth may be closely compressed, or more
commonly the lips are retracted, with the teeth clenched or ground
together. There is said to be “gnashing of teeth” in hell; and I have
plainly heard the grinding of the molar teeth of a cow which was suffering
acutely from inflammation of the bowels. The female hippopotamus in the
Zoological Gardens, when she produced her young, suffered greatly; she
incessantly walked about, or rolled on her sides, opening and closing her
jaws, and clattering her teeth together.[304] With man the eyes
stare wildly as in horrified astonishment, or the brows are heavily
contracted. Perspiration bathes the body, and drops trickle down the face.
The circulation and respiration are much affected. Hence the nostrils are
generally dilated and often quiver; or the breath may be held until the
blood stagnates in the purple face. If the agony be severe and prolonged,
these signs all change; utter prostration follows, with fainting or
convulsions.

A sensitive nerve when irritated transmits some influence to the
nerve-cell, whence it proceeds; and this transmits its influence, first to
the corresponding nerve-cell on the opposite side of the body, and then
upwards and downwards along the cerebro-spinal column to other
nerve-cells, to a greater or less extent, according to the strength of the
excitement; so that, ultimately, the whole nervous system maybe affected.[305]
This involuntary transmission of nerve-force may or may not be accompanied
by consciousness. Why the irritation of a nerve-cell should generate or
liberate nerve-force is not known; but that this is the case seems to be
the conclusion arrived at by all the greatest physiologists, such as
Müller, Virchow, Bernard, &c.[306] As Mr. Herbert
Spencer remarks, it may be received as an “unquestionable truth that, at
any moment, the existing quantity of liberated nerve-force, which in an
inscrutable way produces in us the state we call feeling, MUST expend
itself in some direction—MUST generate an equivalent manifestation
of force somewhere;” so that, when the cerebro-spinal system is highly
excited and nerve-force is liberated in excess, it may be expended in
intense sensations, active thought, violent movements, or increased
activity of the glands.[307] Mr. Spencer further maintains that an
“overflow of nerve-force, undirected by any motive, will manifestly take
the most habitual routes; and, if these do not suffice, will next overflow
into the less habitual ones.” Consequently the facial and respiratory
muscles, which are the most used, will be apt to be first brought into
action; then those of the upper extremities, next those of the lower, and
finally those of the whole body.[308]

An emotion may be very strong, but it will have little tendency to induce
movements of any kind, if it has not commonly led to voluntary action for
its relief or gratification; and when movements are excited, their nature
is, to a large extent, determined by those which have often and
voluntarily been performed for some definite end under the same emotion.
Great pain urges all animals, and has urged them during endless
generations, to make the most violent and diversified efforts to escape
from the cause of suffering. Even when a limb or other separate part of
the body is hurt, we often see a tendency to shake it, as if to shake off
the cause, though this may obviously be impossible. Thus a habit of
exerting with the utmost force all the muscles will have been established,
whenever great suffering is experienced. As the muscles of the chest and
vocal organs are habitually used, these will be particularly liable to be
acted on, and loud, harsh screams or cries will be uttered. But the
advantage derived from outcries has here probably come into play in an
important manner; for the young of most animals, when in distress or
danger, call loudly to their parents for aid, as do the members of the
same community for mutual aid.

Another principle, namely, the internal consciousness that the power or
capacity of the nervous system is limited, will have strengthened, though
in a subordinate degree, the tendency to violent action under extreme
suffering. A man cannot think deeply and exert his utmost muscular force.
As Hippocrates long ago observed, if two pains are felt at the same time,
the severer one dulls the other. Martyrs, in the ecstasy of their
religious fervour have often, as it would appear, been insensible to the
most horrid tortures. Sailors who are going to be flogged sometimes take a
piece of lead into their mouths, in order to bite it with their utmost
force, and thus to bear the pain. Parturient women prepare to exert their
muscles to the utmost in order to relieve their sufferings.

We thus see that the undirected radiation of nerve-force from the
nerve-cells which are first affected—the long-continued habit of
attempting by struggling to escape from the cause of suffering—and
the consciousness that voluntary muscular exertion relieves pain, have all
probably concurred in giving a tendency to the most violent, almost
convulsive, movements under extreme suffering; and such movements,
including those of the vocal organs, are universally recognized as highly
expressive of this condition.

As the mere touching of a sensitive nerve reacts in a direct manner on the
heart, severe pain will obviously react on it in like manner, but far more
energetically. Nevertheless, even in this case, we must not overlook the
indirect effects of habit on the heart, as we shall see when we consider
the signs of rage.

When a man suffers from an agony of pain, the perspiration often trickles
down his face; and I have been assured by a veterinary surgeon that he has
frequently seen drops falling from the belly and running down the inside
of the thighs of horses, and from the bodies of cattle, when thus
suffering. He has observed this, when there has been no struggling which
would account for the perspiration. The whole body of the female
hippopotamus, before alluded to, was covered with red-coloured
perspiration whilst giving birth to her young. So it is with extreme fear;
the same veterinary has often seen horses sweating from this cause; as has
Mr. Bartlett with the rhinoceros; and with man it is a well-known symptom.
The cause of perspiration bursting forth in these cases is quite obscure;
but it is thought by some physiologists to be connected with the failing
power of the capillary circulation; and we know that the vasomotor system,
which regulates the capillary circulation, is much influenced by the mind.
With respect to the movements of certain muscles of the face under great
suffering, as well as from other emotions, these will be best considered
when we treat of the special expressions of man and of the lower animals.

We will now turn to the characteristic symptoms of Rage. Under this
powerful emotion the action of the heart is much accelerated,[309]
or it may be much disturbed. The face reddens, or it becomes purple from
the impeded return of the blood, or may turn deadly pale. The respiration
is laboured, the chest heaves, and the dilated nostrils quiver. The whole
body often trembles. The voice is affected. The teeth are clenched or
ground together, and the muscular system is commonly stimulated to
violent, almost frantic action. But the gestures of a man in this state
usually differ from the purposeless writhings and struggles of one
suffering from an agony of pain; for they represent more or less plainly
the act of striking or fighting with an enemy.

All these signs of rage are probably in large part, and some of them
appear to be wholly, due to the direct action of the excited sensorium.
But animals of all kinds, and their progenitors before them, when attacked
or threatened by an enemy, have exerted their utmost powers in fighting
and in defending themselves. Unless an animal does thus act, or has the
intention, or at least the desire, to attack its enemy, it cannot properly
be said to be enraged. An inherited habit of muscular exertion will thus
have been gained in association with rage; and this will directly or
indirectly affect various organs, in nearly the same manner as does great
bodily suffering.

The heart no doubt will likewise be affected in a direct manner; but it
will also in all probability be affected through habit; and all the more
so from not being under the control of the will. We know that any great
exertion which we voluntarily make, affects the heart, through mechanical
and other principles which need not here be considered; and it was shown
in the first chapter that nerve-force flows readily through habitually
used channels,—through the nerves of voluntary or involuntary
movement, and through those of sensation. Thus even a moderate amount of
exertion will tend to act on the heart; and on the principle of
association, of which so many instances have been given, we may feel
nearly sure that any sensation or emotion, as great pain or rage, which
has habitually led to much muscular action, will immediately influence the
flow of nerve-force to the heart, although there may not be at the time
any muscular exertion.

The heart, as I have said, will be all the more readily affected through
habitual associations, as it is not under the control of the will. A man
when moderately angry, or even when enraged, may command the movements of
his body, but he cannot prevent his heart from beating rapidly. His chest
will perhaps give a few heaves, and his nostrils just quiver, for the
movements of respiration are only in part voluntary. In like manner those
muscles of the face which are least obedient to the will, will sometimes
alone betray a slight and passing emotion. The glands again are wholly
independent of the will, and a man suffering from grief may command his
features, but cannot always prevent the tears from coming into his eyes. A
hungry man, if tempting food is placed before him, may not show his hunger
by any outward gesture, but he cannot check the secretion of saliva.

Under a transport of Joy or of vivid Pleasure, there is a strong tendency
to various purposeless movements, and to the utterance of various sounds.
We see this in our young children, in their loud laughter, clapping of
hands, and jumping for joy; in the bounding and barking of a dog when
going out to walk with his master; and in the frisking of a horse when
turned out into an open field. Joy quickens the circulation, and this
stimulates the brain, which again reacts on the whole body. The above
purposeless movements and increased heart-action may be attributed in
chief part to the excited state of the sensorium,[310] and to the
consequent undirected overflow, as Mr. Herbert Spencer insists, of
nerve-force. It deserves notice, that it is chiefly the anticipation of a
pleasure, and not its actual enjoyment, which leads to purposeless and
extravagant movements of the body, and to the utterance of various sounds.
We see this in our children when they expect any great pleasure or treat;
and dogs, which have been bounding about at the sight of a plate of food,
when they get it do not show their delight by any outward sign, not even
by wagging their tails. Now with animals of all kinds, the acquirement of
almost all their pleasures, with the exception of those of warmth and
rest, are associated, and have long been associated with active movements,
as in the hunting or search for food, and in their courtship. Moreover,
the mere exertion of the muscles after long rest or confinement is in
itself a pleasure, as we ourselves feel, and as we see in the play of
young animals. Therefore on this latter principle alone we might perhaps
expect, that vivid pleasure would be apt to show itself conversely in
muscular movements.

With all or almost all animals, even with birds, Terror causes the body to
tremble. The skin becomes pale, sweat breaks out, and the hair bristles.
The secretions of the alimentary canal and of the kidneys are increased,
and they are involuntarily voided, owing to the relaxation of the
sphincter muscles, as is known to be the case with man, and as I have seen
with cattle, dogs, cats, and monkeys. The breathing is hurried. The heart
beats quickly, wildly, and violently; but whether it pumps the blood more
efficiently through the body may be doubted, for the surface seems
bloodless and the strength of the muscles soon fails. In a frightened
horse I have felt through the saddle the beating of the heart so plainly
that I could have counted the beats. The mental faculties are much
disturbed. Utter prostration soon follows, and even fainting. A terrified
canary-bird has been seen not only to tremble and to turn white about the
base of the bill, but to faint;[311] and I once caught a
robin in a room, which fainted so completely, that for a time I thought it
dead.

Most of these symptoms are probably the direct result, independently of
habit, of the disturbed state of the sensorium; but it is doubtful whether
they ought to be wholly thus accounted for. When an animal is alarmed it
almost always stands motionless for a moment, in order to collect its
senses and to ascertain the source of danger, and sometimes for the sake
of escaping detection. But headlong flight soon follows, with no
husbanding of the strength as in fighting, and the animal continues to fly
as long as the danger lasts, until utter prostration, with failing
respiration and circulation, with all the muscles quivering and profuse
sweating, renders further flight impossible. Hence it does not seem
improbable that the principle of associated habit may in part account for,
or at least augment, some of the above-named characteristic symptoms of
extreme terror.

That the principle of associated habit has played an important part in
causing the movements expressive of the foregoing several strong emotions
and sensations, we may, I think, conclude from considering firstly, some
other strong emotions which do not ordinarily require for their relief or
gratification any voluntary movement; and secondly the contrast in nature
between the so-called exciting and depressing states of the mind. No
emotion is stronger than maternal love; but a mother may feel the deepest
love for her helpless infant, and yet not show it by any outward sign; or
only by slight caressing movements, with a gentle smile and tender eyes.
But let any one intentionally injure her infant, and see what a change!
how she starts up with threatening aspect, how her eyes sparkle and her
face reddens, how her bosom heaves, nostrils dilate, and heart beats; for
anger, and not maternal love, has habitually led to action. The love
between the opposite sexes is widely different from maternal love; and
when lovers meet, we know that their hearts beat quickly, their breathing
is hurried, and their faces flush; for this love is not inactive like that
of a mother for her infant.

A man may have his mind filled with the blackest hatred or suspicion, or
be corroded with envy or jealousy, but as these feelings do not at once
lead to action, and as they commonly last for some time, they are not
shown by any outward sign, excepting that a man in this state assuredly
does not appear cheerful or good-tempered. If indeed these feelings break
out into overt acts, rage takes their place, and will be plainly
exhibited. Painters can hardly portray suspicion, jealousy, envy, &c.,
except by the aid of accessories which tell the tale; and poets use such
vague and fanciful expressions as “green-eyed jealousy.” Spenser describes
suspicion as “Foul, ill-favoured, and grim, under his eyebrows looking
still askance,” &c.; Shakespeare speaks of envy “as lean-faced in her
loathsome case;” and in another place he says, “no black envy shall make
my grave;” and again as “above pale envy’s threatening reach.”

Emotions and sensations have often been classed as exciting or depressing.
When all the organs of the body and mind,—those of voluntary and
involuntary movement, of perception, sensation, thought, &c.,—perform
their functions more energetically and rapidly than usual, a man or animal
may be said to be excited, and, under an opposite state, to be depressed.
Anger and joy are from the first exciting emotions, and they naturally
lead, more especially the former, to energetic movements, which react on
the heart and this again on the brain. A physician once remarked to me as
a proof of the exciting nature of anger, that a man when excessively jaded
will sometimes invent imaginary offences and put himself into a passion,
unconsciously for the sake of reinvigorating himself; and since hearing
this remark, I have occasionally recognized its full truth.

Several other states of mind appear to be at first exciting, but soon
become depressing to an extreme degree. When a mother suddenly loses her
child, sometimes she is frantic with grief, and must be considered to be
in an excited state; she walks wildly about, tears her hair or clothes,
and wrings her hands. This latter action is perhaps due to the principle
of antithesis, betraying an inward sense of helplessness and that nothing
can be done. The other wild and violent movements may be in part explained
by the relief experienced through muscular exertion, and in part by the
undirected overflow of nerve-force from the excited sensorium. But under
the sudden loss of a beloved person, one of the first and commonest
thoughts which occurs, is that something more might have been done to save
the lost one. An excellent observer,[312] in describing the
behaviour of a girl at the sudden death of her father, says she “went
about the house wringing her hands like a creature demented, saying ‘It
was her fault;’ ‘I should never have left him;’ ‘If I had only sat up with
him,’” &c. With such ideas vividly present before the mind, there
would arise, through the principle of associated habit, the strongest
tendency to energetic action of some kind.

As soon as the sufferer is fully conscious that nothing can be done, despair or
deep sorrow takes the place of frantic grief. The sufferer sits motionless, or
gently rocks to and fro; the circulation becomes languid; respiration is almost
forgotten, and deep sighs are drawn. All this reacts on the brain, and
prostration soon follows with collapsed muscles and dulled eyes. As associated
habit no longer prompts the sufferer to action, he is urged by his friends to
voluntary exertion, and not to give way to silent, motionless grief. Exertion
stimulates the hear, and this reacts on the brain, and aids the mind to bear
its heavy load.

Pain, if severe, soon induces extreme depression or prostration; but it is
at first a stimulant and excites to action, as we see when we whip a
horse, and as is shown by the horrid tortures inflicted in foreign lands
on exhausted dray-bullocks, to rouse them to renewed exertion. Fear again
is the most depressing of all the emotions; and it soon induces utter,
helpless prostration, as if in consequence of, or in association with, the
most violent and prolonged attempts to escape from the danger, though no
such attempts have actually been made. Nevertheless, even extreme fear
often acts at first as a powerful stimulant. A man or animal driven
through terror to desperation, is endowed with wonderful strength, and is
notoriously dangerous in the highest degree.

On the whole we may conclude that the principle of the direct action of
the sensorium on the body, due to the constitution of the nervous system,
and from the first independent of the will, has been highly influential in
determining many expressions. Good instances are afforded by the trembling
of the muscles, the sweating of the skin, the modified secretions of the
alimentary canal and glands, under various emotions and sensations. But
actions of this kind are often combined with others, which follow from our
first principle, namely, that actions which have often been of direct or
indirect service, under certain states of the mind, in order to gratify or
relieve certain sensations, desires, &c., are still performed under
analogous circumstances through mere habit although of no service. We have
combinations of this kind, at least in part, in the frantic gestures of
rage and in the writhings of extreme pain; and, perhaps, in the increased
action of the heart and of the respiratory organs. Even when these and
other emotions or sensations are aroused in a very feeble manner, there
will still be a tendency to similar actions, owing to the force of
long-associated habit; and those actions which are least under voluntary
control will generally be longest retained. Our second principle of
antithesis has likewise occasionally come into play.

Finally, so many expressive movements can be explained, as I trust will be
seen in the course of this volume, through the three principles which have
now been discussed, that we may hope hereafter to see all thus explained,
or by closely analogous principles. It is, however, often impossible to
decide how much weight ought to be attributed, in each particular case, to
one of our principles, and how much to another; and very many points in
the theory of Expression remain inexplicable.