that it was created by the animal. Dr. Frankland[36] says to this: "An
animal can no more generate an amount of force capable of moving a grain
of sand, than a stone can fall upwards or a locomotive drive a train
without fuel." As the amount of CO{2} exhaled by the lungs is increased
in the exact ratio of work done by the muscle, it cannot be doubted that
the actual force of the muscle is due to the converted potential energy
of the food. Since every exertion of a muscle and nerves involves the
death and decay of those tissues to a certain extent, as shown by the
excretions, Prof. Orton[37] has been led to say: "An animal begins to
die the moment it begins to live." "A muscle," says Barker,[38] "is like
a steam-engine, is a machine for converting the potential energy of
carbon into motion; but unlike a steam-engine, the muscle accomplishes
this conversion directly, the energy not passing through the
intermediate stages of heat. For this reason the muscle is the most
economical producer of mechanical force known." The muscles which give
the downward stroke of the wing of a bird are fastened to the
breastbone, and their power in proportion to the weight of the bird is
as 10,000 to 1. This great power is needed, for the air is 770 times
lighter than water; the hawk being able to travel 150 miles an hour.
The last of the so-called vital forces under consideration, is that
produced by the nerves and nervous centres. Barker says: "In the nerve
which stimulates a muscle to contract, this force is undeniably motion,
since it is propagated along this nerve from one extremity to the
other." This force has been likened unto electricity, the gray or
cellular matter being the battery, the white or fibrous matter the
conductors. Du Bois Reymond[39] has demonstrated that this force is not
electricity, though by showing that its velocity is only ninety-seven
feet a second. The velocity varies, though, in different animals; it is,
according to Prof. Orton,[40] "more rapid in warm-blooded than in
cold-blooded animals, being nearly twice as fast in man as in the frog."
Wheatstone, by his method, gives the velocity of electricity in copper
wire at 62,000 geographical miles per second; but as neither Fizeau,
Gould, Gonnelle and others could arrive at the same result, the method
was shown to be incorrect, and it remained for Dr. Siemen[41] to
discover the true method, which gives the velocity just one-half that of
Wheatstone's estimate, or 31,000 geographical miles per second. In the
opinion of Bence Jones, the propagation of a nervous impulse is a sort
"of successive molecular polarization, like magnetism." But that this
agent is a force as analogous to electricity as is magnetism, is shown
not only by the fact that the transmission of electricity along a nerve
will cause the contraction of a muscle to which it leads, but also by
the important fact discovered by Marshall, that the contraction of a
muscle is excited by diminishing its normal electrical current,[42] a
result which could take place only with a stimulus, says Barker,
"closely allied to electricity. Nerve force must therefore be transmuted
potential energy." Prof. Huxley says,[43] "the results of recent
inquiries into the structure of the nervous system of animals, converge
toward the conclusion that the nerve-fibres which we have hitherto
regarded as ultimate elements of nervous tissue, are not such, but are
simply the visible aggregations of vastly more attenuated filaments, the
diameter of which dwindles down to the limits of our present microscopic
vision, greatly as these have been extended by modern improvements of
the microscope; and that a nerve is, in its essence, nothing but a
linear tract of specially modified protoplasm between two points of an
organism, one of which is able to affect the other by means of the
communication so established. Hence it is conceivable that even the
simplest living being may possess a nervous system."
Herbert Spencer[44] says all direct and indirect evidence "justifies us
in concluding that the nervous system consists of _one_ kind of matter.
In the gray tissue this matter exists in masses containing _corpuscles_,
which are soft and have granules dispersed through them, and which,
besides being thus unstably composed, are placed so as to be liable to
disturbances to the greatest degree. In the white tissue this matter is
collected together in extremely slender _threads_ that are denser, that
are uniform in texture, and that are shielded in an unusual manner from
disturbing forces, except at their two extremities."
The last consideration is that form of force (thought power) which
appears in manifestations called mental. It must be noticed at the
outset, that every external manifestation of thought force is a muscular
one, as a word spoken or written, a gesture, or an expression of the
face always takes place; hence this force must be intimately correlated
to nerve force. It is very certain, then, that thought force is capable
in external manifestations of converting itself into actual motion. But
here the question arises, can it be manifested inwardly without such a
transformation of energy? Or is the evolution of thought entirely
independent of the matter of the brain?
This question can be answered by actual experiment, strange as it may
appear. Experiments have demonstrated that any change of temperature
within the skull was soonest manifested externally in that depression
which exists just above the occipital protuberance. Here Lombard[45]
fastened to the head at this point two little bars, one made of bismuth,
the other of an alloy of antimony and zinc, which were connected with a
delicate galvanometer;[46] to neutralize the result of a gradual rise of
temperature over the whole body, a second pair of bars, reversed in
direction, was attached to the leg or arm, so that if a like increase of
heat came to both, the electricity developed by one would be neutralized
by the other, and no effect would be produced by the needle unless only
one was affected. By long practice it was ascertained that a mental
torpor could be induced, lasting for hours, in which the needle remained
stationary. But let a person knock on the door outside of the room, or
speak a single word, even though the experimenter remained absolutely
passive, the reception of the intelligence caused the needle to swing
twenty degrees. "In explanation of this production of heat," says
Barker,[47] "the analogy of the muscle at once suggests itself. No
conversion of energy is complete, and as the heat of muscular action
represents force which has escaped conversion into motion, so the heat
evolved during the reception of an idea is energy which has escaped
conversion into thought, from precisely the same cause." Dr. Lombard's
experiments have shown that the amount of heat developed by the
recitation to one's self of emotional poetry, was in every case less
when recitation was oral; this is of course accounted for by the
muscular expression. Chemistry teaches that thought-force, like
muscle-force, comes from the food, and demonstrates that the force
evolved by the brain, like that produced by the muscle, comes not from
the disintegration of its own tissue, but is the converted energy of
burning carbon.[48] "Can we longer doubt," says Barker,[49] "that the
brain too, is a machine for the conversion of energy? Can we longer
refuse to believe that even thought force is in some mysterious way
correlated to the other natural forces? and this even in the face of the
fact that it has never yet been measured.[50] Have we not a right to ask
'why a special force (vital force) should be needed to effect the
transformation of physical forces into those modes of energy which are
active in the manifestation of living beings, while no peculiar force is
deemed necessary to effect the transformation of one mode of physical
force into any other mode of physical force?"
Richard Owen says:[51] "In the endeavor to clearly comprehend and
explain the functions of the combination of forces called 'brain,' the
physiologist is hindered and troubled by the views of the nature of
those cerebral forces which the needs of dogmatic theology have imposed
on mankind. * * * Religion, pure and undefiled, can best answer how far
it is righteous or just to charge a neighbor with being unsound in his
principles who holds the term 'life' to be a sound expressing the sum of
living phenomena, and who maintains these phenomena to be modes of
force into which other forms of force have passed from potential to
active states, and reciprocally, through the agency of the sums or
combinations of forces impressing the mind with the ideas signified by
the terms 'monad,' 'moss,' 'plant,' or 'animal.'"
We have now shown that the very forces which give vent to the attributes
of man, are correlated to the physical forces. Let us now consider his
attributes as manifested by his mental powers. There is no doubt the
difference between the mental faculties of the ape and that of the
lowest savage, who cannot express any number higher than four and who
uses hardly any abstract terms for common objects or for the
affections,[52] is still very great and would still be great, says
Darwin, "even if one of the higher apes had been improved or civilized
as much as a dog has been in comparison with its parent form, the wolf
or jackal." But when we examine the interval of mental power between one
of the lowest fishes, as a lamprey or a lancelet, and one of the higher
apes, and recognize the fact that this interval is filled up by
numberless gradations, it does not become so difficult to understand the
interval between an ape and man, which is not by far so great. As in
finding out what is peculiar to a living body in distinction to a body
not living, we found it absurd to take man as the perfection of the
animal scale--the microscopic monad possessing life as well as him--so
in the case of man's mental attributes, which have always been
increasing, always perfecting, since the first genuine man came into
existence, it would be equally absurd to compare the intellectual man of
to-day with an ape to see what attributes he possesses which the ape
does not possess; but if we go down in the scale and compare the savage
with the ape, the difficulty is not by far so great. It will be found
on close examination, though, that man and the higher animals,
especially the primates, have many instincts in common. "All," says
Darwin, "have the same senses, intuitions and sensations; similar
passions, affections, and emotions; even the more complex ones, such as
jealousy, suspicion, emulation, gratitude and magnanimity; they practice
deceit and are revengeful; they are sometimes susceptible to ridicule
and even have a sense of humor; they feel wonder and curiosity; they
possess the same faculties of imitation, attention, deliberation,
choice, memory, imagination, the association of ideas, and reason,
though in very different degrees. The individuals of the same species
graduate in intellect from absolute imbecility to high excellence; they
are also liable to insanity, though far less often than in the case of
man."[53] Nevertheless, in the face of these facts, many authors have
insisted that man is divided by an inseparable barrier from all the
lower animals in his mental faculties. It only shows the improper or
imperfect consideration of the subject they have under discussion.
It may be thought at first that some of the mental attributes mentioned
above are not possessed by animals. I therefore will briefly consider a
few of the more complex ones. We can dismiss the consideration of such
attributes as happiness, terror, suspicion, courage, timidity, jealousy,
shame, and wonder, as well-known attributes. _Curiosity_ in animals is
often observed. An instance mentioned by Brehm will serve to illustrate:
Brehm gives a curious account of the instinctive dread which his monkeys
exhibited for snakes; but their curiosity was so great that they could
not desist from occasionally satiating their horror in a most human
fashion, by lifting up the lid of the box in which the snakes were kept.
_Imitation_ is also found among the action of animals, especially among
monkeys, which are well known to be ridiculous mockers.
It is unnecessary to refer to the faculty of attention, as it is common
to almost all animals, and the same may be said of memory as for persons
or places.
One would hesitate to believe an animal possesses _imagination_, but
such is the case. Dreaming, it will be admitted, gives us the best
notion of this power. Now as dogs, cats, horses, and probably all the
higher animals, even birds, have vivid dreams--this is shown by their
movements and the sounds uttered--"we must admit," says Darwin, "they
possess some power of imagination. There must be something special which
causes dogs to howl in the night, and especially during moonlight, in
that remarkable and melancholy manner, called baying. All dogs do not do
so; and, according to Housyeau,[54] they do not look at the moon, but at
some fixed point near the horizon. Housyeau thinks that their
imaginations are disturbed by the vague outlines of the surrounding
objects, and conjure up before them fantastic images; if this be so,
their feelings may almost be called superstitious."
The next mental faculty is _reason_, which stands at the summit; but
still there are few persons who will deny that animals possess some
power of reasoning. A few illustrations will be all that is necessary to
satisfy the inquiring mind on this point. Reugger, a most careful
observer, states that when he first gave eggs to his monkey in Paraguay
they smashed them, and thus lost much of their contents; afterward they
gently hit one end against some hard body, and picked off the bits of
shell with their fingers. After cutting themselves _once_ with any sharp
tool, they would not touch it again, or would handle it with the
greatest caution. Lumps of sugar were often given them, wrapped up in
paper; and Reugger sometimes put a live wasp in the paper, so that in
hastily unfolding it they got stung; after this had _once_ happened,
they afterward first held the packet to their ears to detect any
movement within.
The following cases relating to dogs are described by Darwin: Mr.
Colquhoun winged two wild ducks, which fell on the farther side of a
stream; his retriever tried to bring over both at once, but could not
succeed; she then, though never before known to ruffle a feather,
deliberately killed one, brought over the other, and returned for the
dead bird. Colonel Hutchinson relates that two partridges were shot at
once--one being killed, the other wounded; the latter ran away, and was
caught by the retriever, who, on her return, came across the dead bird;
"she stopped, evidently greatly puzzled, and after one or two trials,
finding she could not take it up without permitting the escape of the
winged bird, she considered a moment, then deliberately murdered it by
giving it a severe crunch, and afterward brought away both together.
This was the only known instance of her ever having wilfully injured any
game. Here we have reason, though not quite perfect; for the retriever
might have brought the wounded bird first, and then returned for the
dead one, as in the case of the two wild ducks. I give the above cases
as resting on the evidence of two independent witnesses; and because in
both instances the retrievers, after deliberation, broke through a habit
which was inherited by them (that of not killing the game retrieved),
and because they show how strong their reasoning faculty must have been
to overcome a fixed habit."[55]
It has often been said that no animal uses any tool, but this can be so
easily refuted on reflection, that it is hardly worth while considering;
for illustration, though, the chimpanzee in a state of nature cracks
nuts with a stone; Darwin saw a young orang put a stick in a crevice,
slip his hand to the other end, and use it in a proper manner as a
lever. The baboons in Abyssinia descend in troops from the mountains to
plunder fields, and when they meet troops of another species a fight
ensues. They commence by rolling great stones at their enemies, as they
often do when attacked with fire-arms.
The Duke of Argyll remarks that the fashioning of an implement for a
special purpose is absolutely peculiar to man; and he considers this
forms an immeasurable gulf between him and the brutes. "This is no
doubt," says Darwin, "a very important distinction; but there appears to
me much truth in Sir J. Lubbock's suggestion,[56] that when primeval man
first used flint-stones for any purpose, he would have accidentally
splintered them, and would then have used the sharp fragments. From this
step it would be a small one to break the flints on purpose, and not a
very wide step to fashion them rudely. The later advance, however, may
have taken long ages, if we may judge by the immense interval of time
which elapsed before the men of the neolithic period took to grinding
and polishing their stone tools. In breaking the flints, as Sir J.
Lubbock likewise remarks, sparks would have been emitted, and in
grinding them heat would have been evolved; thus the two usual methods
of 'obtaining fire may have originated.' The nature of fire would have
been known in many volcanic regions where lava occasionally flows
through forests."
It becomes a difficult task to determine how far animals exhibit any
traces of such high faculties as _abstraction_, _general conception_,
_self-consciousness_, _mental individuality_. There can be no doubt, if
the mental faculties of an animal can be improved, that the higher
complex faculties such as abstraction and self-consciousness have
developed from a combination of the simpler ones; this seems to be well
illustrated in the young child, as such faculties are developed by
imperceptible degrees. These high faculties are very sparingly possessed
by the savage; as Buchner[57] has remarked, how little can the
hard-worked wife of a degraded Australian savage, who uses very few
abstract words and cannot count above four, exert her self-consciousness
or reflect on the nature of her own existence. If there exist a class of
people so inferior in their mental faculties as these, it is not
difficult for us to understand how the educated animal who possesses
memory, attention, association, and even some imagination and reason,
can become capable of abstraction, &c., in an inferior degree even to
the savage. It certainly cannot be doubted that an animal possesses
mental individuality--as when a master returns to a dog which he has not
seen for years, and the dog recognizes him at once.
One of the chief distinctions between man and animals is the faculty of
language. Let us look at this for a moment. "The essential differences,"
says Prof. Whitney, "which separate man's means of communication in kind
as well as degree from that of the other animals is that, while the
latter is instinctive, the former is in all its parts arbitrary and
conventional. No man can become possessed of any language without
learning it; no animal (that we know of) has any expression which he
learns, which is not the direct gift of nature to him." Any child of
parents living in a foreign country grows up to speak the foreign
speech, unless carefully guarded from doing so; or it speaks both this
and the tongue of its parent with equal readiness. A child must learn to
observe and distinguish before speech is possible, and every child
begins to know things by their name before he begins to call them. "If
it were not for the added push," says Prof. Whitney, "given by the
desire of communication, the great and wonderful power of the human
soul would never move in this particular direction; but when this leads
the way, all the rest follows." No philologist now supposes that any
language has been deliberately invented; it has been slowly and
unconsciously developed by many steps.
There can be no question that language owes its origin to the imitation
and modification of various natural sounds, the voices of other animals,
and man's own instinctive cries, aided by signs and gestures; and this
is the opinion of Max Müller. And Prof. Whitney remarks that "spoken
language began, we may say, when a cry of pain, formally wrung out by
real suffering, and seen to be understood and sympathized with, was
repeated in imitation, no longer as a mere instinctive utterance, but
for the purpose of intimating to another." Darwin says that "the early
progenitor of man probably first used his voice in producing true
musical cadences, that is, in singing, as do some gibbon-apes at the
present day. It is therefore probable that the imitation of musical
cries by articulate sounds may have given rise to words expressive of
very complex emotions."
The nearest approach to language are the sounds uttered by birds. All
that sing exert their power instinctively, but the actual song, and even
the call notes, are learned from their parents or foster-parents. These
sounds are no more innate than language is in man, as has been proved by
Davies Barrington.[58] The first attempt to sing "may be compared to the
imperfect endeavor in a child to babble." Prof. Whitney says, if the
last transition forms of man "could be restored, we should find the
transition forms toward our speech to be, not at all a minor provision
of natural articulate signs, but an inferior system of conventional
signs, in tone, gesture, and grimace. As between these three natural
means of expression, it is simply by a kind of process of natural
selection and survival of the fittest that the voice has gained the
upper hand, and come to be so much the most prominent that we give the
name of language (tonguiness) to all expression." A single utterance or
two at first had to do the duty of a whole clause; afterward man learned
to piece together parts of speech, and thus arose sentences.
Although no language, as has already been said, has been deliberately
invented, "still each word may not be unfitly compared to an invention;
it has its own place, mode, and circumstances of devisal, its
preparation in the previous habits of speech, its influence in
determining the after progress of speech development; but every language
in the gross is an institution, on which scores or hundreds of
generations and unnumbered thousands of individual workers have
labored."[59]
There is no question at all but that the mental powers in the earliest
progenitors of man must have been more highly developed than in the ape,
before even the most imperfect form of speech could have come into use;
but the constant advancement of this power would have reacted on the
mind to enable it to carry on longer trains of thought. "A complex train
of thought," says Darwin, "can no more be carried on without the aid of
words, whether spoken or silent, than a long calculation without the use
of figures in algebra. It appears also that even an ordinary train of
thought almost requires or is greatly facilitated by some form of
language; for the dumb, deaf, and blind girl, Laura Bridgman, was
observed to use her fingers while dreaming.[60] Nevertheless a long
succession of vivid ideas may pass through the mind, without the aid of
any form of language, as we may infer from the movements of dogs during
their dreams."
The struggle for existence is going on in every language; one after
another will be swept out of existence, and the languages best fitted
for the practical uses of the masses of people will alone survive. Max
Müller has well remarked: "A struggle for life is constantly going on
amongst the words and grammatical forms in each language. The better the
shorter; the easier forms are constantly gaining the upper hand, and
they owe their success to their own inherent virtue."[61]