turn to the vegetable world. A fluid containing carbonic acid, water,
and nitrogenous salts, which offers such a Barmecide feast[52] to the
animal, is a table richly spread to multitudes of plants; and, with a
due supply of only such materials, many a plant will not only maintain
itself in vigour, but grow and multiply until it has increased a
million-fold, or a million million-fold, the quantity of protoplasm
which it originally possessed; in this way building up the matter of
life, to an indefinite extent, from the common matter of the universe.
Thus, the animal can only raise the complex substance of dead protoplasm
to the higher power, as one may say, of living protoplasm; while the
plant can raise the less complex substances--carbonic acid, water, and
nitrogenous salts--to the same stage of living protoplasm, if not to the
same level. But the plant also has its limitations. Some of the fungi,
for example, appear to need higher compounds to start with; and no known
plant can live upon the uncompounded elements of protoplasm. A plant
supplied with pure carbon, hydrogen, oxygen, and nitrogen, phosphorus,
sulphur, and the like, would as infallibly die as the animal in his bath
of smelling-salts, though it would be surrounded by all the constituents
of protoplasm. Nor, indeed, need the process of simplification of
vegetable food be carried so far as this, in order to arrive at the
limit of the plant's thaumaturgy. Let water, carbonic acid, and all the
other needful constituents be supplied except nitrogenous salts, and an
ordinary plant will still be unable to manufacture protoplasm.
Thus the matter of life, so far as we know it (and we have no right to
speculate on any other), breaks up, in consequence of that continual
death which is the condition of its manifesting vitality, into carbonic
acid, water, and nitrogenous compounds, which certainly possess no
properties but those of ordinary matter. And out of these same forms of
ordinary matter, and from none which are simpler, the vegetable world
builds up all the protoplasm which keeps the animal world a-going.
Plants are the accumulators of the power which animals distribute and
disperse.
But it will be observed, that the existence of the matter of life
depends on the pre-existence of certain compounds; namely, carbonic
acid, water, and certain nitrogenous bodies. Withdraw any one of these
three from the world, and all vital phenomena come to an end. They are
as necessary to the protoplasm of the plant, as the protoplasm of the
plant is to that of the animal. Carbon, hydrogen, oxygen, and nitrogen
are all lifeless bodies. Of these, carbon and oxygen unite in certain
proportions and under certain conditions, to give rise to carbonic acid;
hydrogen and oxygen produce water; nitrogen and other elements give rise
to nitrogenous salts. These new compounds, like the elementary bodies of
which they are composed, are lifeless. But when they are brought
together, under certain conditions, they give rise to the still more
complex body, protoplasm, and this protoplasm exhibits the phenomena of
life.
I see no break in this series of steps in molecular complication, and I
am unable to understand why the language which is applicable to any one
term of the series may not be used to any of the others. We think fit to
call different kinds of matter carbon, oxygen, hydrogen, and nitrogen,
and to speak of the various powers and activities of these substances as
the properties of the matter of which they are composed.
When hydrogen and oxygen are mixed in a certain proportion, and an
electric spark is passed through them, they disappear, and a quantity of
water, equal in weight to the sum of their weights, appears in their
place. There is not the slightest parity between the passive and active
powers of the water and those of the oxygen and hydrogen which have
given rise to it. At 32° Fahrenheit, and far below that temperature,
oxygen and hydrogen are elastic gaseous bodies, whose particles tend to
rush away from one another with great force. Water, at the same
temperature, is a strong though brittle solid, whose particles tend to
cohere into definite geometrical shapes, and sometimes build up frosty
imitations of the most complex forms of vegetable foliage.
Nevertheless we call these, and many other strange phenomena, the
properties of the water, and we do not hesitate to believe that, in some
way or another, they result from the properties of the component
elements of the water. We do not assume that a something called
"aquosity" entered into and took possession of the oxidated hydrogen as
soon as it was formed, and then guided the aqueous particles to their
places in the facets of the crystal, or amongst the leaflets of the
hoar-frost. On the contrary, we live in the hope and in the faith that,
by the advance of molecular physics, we shall by and by be able to see
our way as clearly from the constituents of water to the properties of
water, as we are now able to deduce the operations of a watch from the
form of its parts and the manner in which they are put together.
Is the case in any way changed when carbonic acid, water, and
nitrogenous salts disappear, and in their place, under the influence of
pre-existing living protoplasm, an equivalent weight of the matter of
life makes its appearance?
It is true that there is no sort of parity between the properties of the
components and the properties of the resultant, but neither was there in
the case of the water. It is also true that what I have spoken of as the
influence of pre-existing living matter is something quite
unintelligible; but does anybody quite comprehend the _modus
operandi_[53] of an electric spark, which traverses a mixture of oxygen
and hydrogen?
What justification is there, then, for the assumption of the existence
in the living matter of a something which has no representative, or
correlative, in the not living matter which gave rise to it? What better
philosophical status has "vitality" than "aquosity"? And why should
"vitality" hope for a better fate than the other "itys" which have
disappeared since Martinus Scriblerus accounted for the operation of the
meat-jack by its inherent "meat-roasting quality," and scorned the
"materialism" of those who explained the turning of the spit by a
certain mechanism worked by the draught of the chimney?
If scientific language is to possess a definite and constant
signification whenever it is employed, it seems to me that we are
logically bound to apply to the protoplasm, or physical basis of life,
the same conceptions as those which are held to be legitimate elsewhere.
If the phenomena exhibited by water are its properties, so are those
presented by protoplasm, living or dead, its properties.
If the properties of water may be properly said to result from the
nature and disposition of its component molecules, I can find no
intelligible ground for refusing to say that the properties of
protoplasm result from the nature and disposition of its molecules.
But I bid you beware that, in accepting these conclusions, you are
placing your feet on the first rung of a ladder which, in most people's
estimation, is the reverse of Jacob's and leads to the antipodes of
heaven. It may seem a small thing to admit that the dull vital actions
of a fungus, or a foraminifer, are the properties of their protoplasm,
and are the direct results of the nature of the matter of which they are
composed. But if, as I have endeavoured to prove to you, their
protoplasm is essentially identical with, and most readily converted
into, that of any animal, I can discover no logical halting-place
between the admission that such is the case, and the further concession
that all vital action may, with equal propriety, be said to be the
result of the molecular forces of the protoplasm which displays it. And
if so, it must be true, in the same sense and to the same extent, that
the thoughts to which I am now giving utterance, and your thoughts
regarding them, are the expression of molecular changes in that matter
of life which is the source of our other vital phenomena.
Past experience leads me to be tolerably certain that, when the
propositions I have just placed before you are accessible to public
comment and criticism, they will be condemned by many zealous persons,
and perhaps by some few of the wise and thoughtful. I should not wonder
if "gross and brutal materialism" were the mildest phrase applied to
them in certain quarters. And, most undoubtedly, the terms of the
propositions are distinctly materialistic. Nevertheless two things are
certain: the one, that I hold the statements to be substantially true;
the other, that I, individually, am no materialist, but, on the
contrary, believe materialism to involve grave philosophical error.
This union of materialistic terminology with the repudiation of
materialistic philosophy I share with some of the most thoughtful men
with whom I am acquainted. And, when I first undertook to deliver the
present discourse, it appeared to me to be a fitting opportunity to
explain how such a union is not only consistent with, but necessitated
by, sound logic. I purposed to lead you through the territory of vital
phenomena to the materialistic slough in which you find yourselves now
plunged, and then to point out to you the sole path by which, in my
judgment, extrication is possible.
* * * * *
Let us suppose that knowledge is absolute, and not relative, and
therefore, that our conception of matter represents that which it really
is. Let us suppose, further, that we do know more of cause and effect
than a certain definite order of succession among facts, and that we
have a knowledge of the necessity of that succession--and hence, of
necessary laws--and I, for my part, do not see what escape there is from
utter materialism and necessarianism. For it is obvious that our
knowledge of what we call the material world is, to begin with, at least
as certain and definite as that of the spiritual world, and that our
acquaintance with law is of as old a date as our knowledge of
spontaneity. Further, I take it to be demonstrable that it is utterly
impossible to prove that anything whatever may not be the effect of a
material and necessary cause, and that human logic is equally
incompetent to prove that any act is really spontaneous. A really
spontaneous act is one which, by the assumption, has no cause; and the
attempt to prove such a negative as this is, on the face of the matter,
absurd. And while it is thus a philosophical impossibility to
demonstrate that any given phenomenon is not the effect of a material
cause, any one who is acquainted with the history of science will admit,
that its progress has, in all ages, meant, and now, more than ever,
means, the extension of the province of what we call matter and
causation, and the concomitant gradual banishment from all regions of
human thought of what we call spirit and spontaneity.
I have endeavoured, in the first part of this discourse, to give you a
conception of the direction towards which modern physiology is tending;
and I ask you, what is the difference between the conception of life as
the product of a certain disposition of material molecules, and the old
notion of an Archaeus[54] governing and directing blind matter within
each living body, except this--that here, as elsewhere, matter and law
have devoured spirit and spontaneity? And as surely as every future
grows out of past and present, so will the physiology of the future
gradually extend the realm of matter and law until it is co-extensive
with knowledge, with feeling, and with action.
The consciousness of this great truth weighs like a nightmare, I
believe, upon many of the best minds of these days. They watch what they
conceive to be the progress of materialism, in such fear and powerless
anger as a savage feels when, during an eclipse, the great shadow creeps
over the face of the sun. The advancing tide of matter threatens to
drown their souls; the tightening grasp of law impedes their freedom;
they are alarmed lest man's moral nature be debased by the increase of
his wisdom.
If the "New Philosophy" be worthy of the reprobation with which it is
visited, I confess their fears seem to me to be well founded. While, on
the contrary, could David Hume be consulted, I think he would smile at
their perplexities, and chide them for doing even as the heathen, and
falling down in terror before the hideous idols their own hands have
raised.
For, after all, what do we know of this terrible "matter," except as a
name for the unknown and hypothetical cause of states of our own
consciousness? And what do we know of that "spirit" over whose
threatened extinction by matter a great lamentation is arising, like
that which was heard at the death of Pan, except that it is also a name
for an unknown and hypothetical cause, or condition, of states of
consciousness? In other words, matter and spirit are but names for the
imaginary substrata of groups of natural phenomena.
And what is the dire necessity and "iron" law under which men groan?
Truly, most gratuitously invented bugbears. I suppose if there be an
"iron" law, it is that of gravitation; and if there be a physical
necessity, it is that a stone, unsupported, must fall to the ground. But
what is all we really know, and can know, about the latter phenomenon?
Simply, that, in all human experience, stones have fallen to the ground
under these conditions; that we have not the smallest reason for
believing that any stone so circumstanced will not fall to the ground;
and that we have, on the contrary, every reason to believe that it will
so fall. It is very convenient to indicate that all the conditions of
belief have been fulfilled in this case, by calling the statement that
unsupported stones will fall to the ground, "a law of Nature." But when,
as commonly happens, we change _will_ into _must_, we introduce an idea
of necessity which most assuredly does not lie in the observed facts,
and has no warranty that I can discover elsewhere. For my part, I
utterly repudiate and anathematise the intruder. Fact I know; and Law I
know; but what is this Necessity save an empty shadow of my own mind's
throwing?
But, if it is certain that we can have no knowledge of the nature of
either matter or spirit, and that the notion of necessity is something
illegitimately thrust into the perfectly legitimate conception of law,
the materialistic position that there is nothing in the world but
matter, force, and necessity, is as utterly devoid of justification as
the most baseless of theological dogmas. The fundamental doctrines of
materialism, like those of spiritualism, and most other "isms," lie
outside "the limits of philosophical inquiry," and David Hume's great
service to humanity is his irrefragable demonstration of what these
limits are. Hume called himself a sceptic, and therefore others cannot
be blamed if they apply the same title to him; but that does not alter
the fact that the name, with its existing implications, does him gross
injustice.
If a man asks me what the politics of the inhabitants of the moon are,
and I reply that I do not know; that neither I, nor any one else, has
any means of knowing; and that, under these circumstances, I decline to
trouble myself about the subject at all; I do not think he has any right
to call me a sceptic. On the contrary, in replying thus, I conceive that
I am simply honest and truthful, and show a proper regard for the
economy of time. So Hume's strong and subtle intellect takes up a great
many problems about which we are naturally curious, and shows us that
they are essentially questions of lunar politics, in their essence
incapable of being answered, and therefore not worth the attention of
men who have work to do in the world. And he thus ends one of his
essays:--
"If we take in hand any volume of Divinity, or school metaphysics, for
instance, let us ask, _Does it contain any abstract reasoning concerning
quantity or number?_ No. _Does it contain any experimental reasoning
concerning matter of fact and existence?_ No. Commit it then to the
flames; for it can contain nothing but sophistry and illusion."[55]
Permit me to enforce this most wise advice. Why trouble ourselves about
matters of which, however important they may be, we do know nothing, and
can know nothing? We live in a world which is full of misery and
ignorance, and the plain duty of each and all of us is to try to make
the little corner he can influence somewhat less miserable and somewhat
less ignorant than it was before he entered it. To do this effectually
it is necessary to be fully possessed of only two beliefs: the first,
that the order of Nature is ascertainable by our faculties to an extent
which is practically unlimited; the second, that our volition[56] counts
for something as a condition of the course of events.
Each of these beliefs can be verified experimentally, as often as we
like to try. Each, therefore, stands upon the strongest foundation upon
which any belief can rest, and forms one of our highest truths. If we
find that the ascertainment of the order of nature is facilitated by
using one terminology, or one set of symbols, rather than another, it is
our clear duty to use the former; and no harm can accrue, so long as we
bear in mind that we are dealing merely with terms and symbols.
In itself it is of little moment whether we express the phenomena of
matter in terms of spirit; or the phenomena of spirit in terms of
matter: matter may be regarded as a form of thought, thought may be
regarded as a property of matter--each statement has a certain relative
truth. But with a view to the progress of science, the materialistic
terminology is in every way to be preferred. For it connects thought
with the other phenomena of the universe, and suggests inquiry into the
nature of those physical conditions, or concomitants of thought, which
are more or less accessible to us, and a knowledge of which may, in
future, help us to exercise the same kind of control over the world of
thought as we already possess in respect of the material world;
whereas, the alternative, or spiritualistic, terminology is utterly
barren, and leads to nothing but obscurity and confusion of ideas.
Thus there can be little doubt, that the further science advances, the
more extensively and consistently will all the phenomena of Nature be
represented by materialistic formulae and symbols.
But the man of science, who, forgetting the limits of philosophical
inquiry, slides from these formulae and symbols into what is commonly
understood by materialism, seems to me to place himself on a level with
the mathematician who should mistake the x's and y's with which he works
his problems, for real entities--and with this further disadvantage, as
compared with the mathematician, that the blunders of the latter are of
no practical consequence, while the errors of systematic materialism may
paralyse the energies and destroy the beauty of a life.
FOOTNOTES:
[Footnote 48: The substance of this paper was contained in an address
which was delivered in Edinburgh in 1868. The paper was published in
"Lay Sermons," 1870.]
[Footnote 49: _à fortiori:_ with stronger reason.]
[Footnote 50: Why does the populace rush so and make clamor? It wishes
to eat, bring forth children, and feed these as well as it may.... No
man can do better, strive how he will.]
[Footnote 51: We and ours must die.]
[Footnote 52: In one of the Arabian Nights stories, a nobleman called
Barmecide set before a beggar a number of empty dishes supposed to
contain a feast.]
[Footnote 53: Mode of working.]
[Footnote 54: Archaeus: a spirit, having essentially the same form as
the body within which it resided.]
[Footnote 55: Hume's Essay "Of the Academical or Sceptical Philosophy,"
in the _Inquiry concerning the Human Understanding._--[Many critics of
this passage seem to forget that the subject-matter of Ethics and
Aesthetics consists of matters of fact and existence.--1892.]--Author's
note.]
[Footnote 56: Or, to speak more accurately, the physical state of which
volition is the expression.--1892.--Author's note.]
COMPARISON OF THE MENTAL POWERS OF MAN AND THE LOWER ANIMALS[57]
CHARLES DARWIN
My object in this chapter is to show that there is no fundamental
difference between man and the higher mammals in their mental faculties.
Each division of the subject might have been extended into a separate
essay, but must here be treated briefly. As no classification of the
mental powers has been universally accepted, I shall arrange my remarks
in the order most convenient for my purpose; and will select those facts
which have struck me most, with the hope that they may produce some
effect on the reader.
As man possesses the same senses as the lower animals, his fundamental
intuitions must be the same. Man has also some few instincts in common,
as that of self-preservation, sexual love, the love of the mother for
her new-born offspring, the desire possessed by the latter to suck, and
so forth. But man, perhaps, has somewhat fewer instincts: than those
possessed by the animals which come next to him in the series. The orang
in the Eastern islands and the chimpanzee in Africa build platforms on
which they sleep; and as both species follow the same habit, it might be
argued that this was due to instinct, but we cannot feel sure that it is
not the result of both animals having similar wants and possessing
similar powers of reasoning. These apes, as we may assume, avoid the
many poisonous fruits of the tropics, and man has no such knowledge; but
as our domestic animals, when taken to foreign lands, and when first
turned out in the spring, often eat poisonous herbs, which they
afterward avoid, we cannot feel sure that the apes do not learn from
their own experience or from that of their parents what fruits to
select. It is, however, certain, as we shall presently see, that apes
have an instinctive dread of serpents, and probably of other dangerous
animals.
The fewness and the comparative simplicity of the instincts in the
higher animals are remarkable in contrast with those of the lower
animals. Cuvier maintained that instinct and intelligence stand in an
inverse ratio to each other; and some have thought that the intellectual
faculties of the higher animals have been gradually developed from their
instincts. But Pouchet, in an interesting essay, has shown that no such
inverse ratio really exists. Those insects which possess the most
wonderful instincts are certainly the most intelligent. In the
vertebrate series, the least intelligent members, namely fishes and
amphibians, do not possess complex instincts; and among mammals the
animal most remarkable for its instincts, namely the beaver, is highly
intelligent, as will be admitted by every one who has read Mr. Morgan's
excellent work.[58]
But although, as we learn from the above-mentioned insects and the
beaver, a high degree of intelligence is certainly compatible with
complex instincts, and although actions, at first learned voluntarily,
can soon through habit be performed with the quickness and certainty of
a reflex action, yet it is not improbable that there is a certain amount
of interference between the development of free intelligence and of
instinct, since the latter implies some inherited modification of the
brain. Little is known about the functions of the brain, but we can
perceive that as the intellectual powers become highly developed the
various parts of the brain must be connected by very intricate channels
of the freest intercommunication; and as a consequence each separate
part would perhaps tend to be less well fitted to answer to particular
sensations or associations in a definite and inherited--that is,
instinctive--manner. There seems even to exist some relation between a
low degree of intelligence and a strong tendency to the formation of
fixed, though not inherited, habits; for as a sagacious physician
remarked to me, persons who are slightly imbecile tend to act in
everything by routine or habit; and they are rendered much happier if
this is encouraged.