An impulse inherent in primeval man turned his thoughts and
questionings betimes towards the sources of natural phenomena. The
same impulse, inherited and intensified, is the spur of scientific
action to-day. Determined by it, by a process of abstraction from
experience we form physical theories which lie beyond the pale of
experience, but which satisfy the desire of the mind to see every
natural occurrence resting upon a cause. In forming their notions of
the origin of things, our earliest historic (and doubtless, we might
add, our prehistoric) ancestors pursued, as far as their intelligence
permitted, the same course. They also fell back upon experience, but
with this difference--that the particular experiences which furnished
the weft and woof of their theories were drawn, not from the study of
nature, but from what lay much closer to them, the observation of
men. Their theories accordingly took an anthropomorphic form. To
supersensual beings, which, 'however potent and invisible, were
nothing but a species of human creatures, perhaps raised from among
mankind, and retaining all human passions and appetites,'[1] were
handed over the rule and governance of natural phenomena.
Tested by observation and reflection, these early notions failed in
the long run to satisfy the more penetrating intellects of our race.
Far in the depths of history we find men of exceptional power
differentiating themselves from the crowd, rejecting these
anthropomorphic notions, and seeking to connect natural phenomena
with their physical principles. But long prior to these purer
efforts of the understanding the merchant had been abroad, and
rendered the philosopher possible; commerce had been developed,
wealth amassed, leisure for travel and speculation secured, while
races educated under different conditions, and therefore differently
informed and endowed, had been stimulated and sharpened by mutual
contact. In those regions where the commercial aristocracy of
ancient Greece mingled with its eastern neighbours the sciences were
born, being nurtured and developed by free-thinking and courageous
men. The state of things to be displaced may be gathered from a
passage of Euripides quoted by Hume. 'There is nothing in the world;
no glory, no prosperity. The gods toss all into confusion; mix
everything with its reverse, that all of us, from our ignorance and
uncertainty, may pay them the more worship and reverence.' Now, as
science demands the radical extirpation of caprice and the absolute
reliance upon law in nature, there grew with the growth of scientific
notions a desire and determination to sweep from the field of theory
this mob of gods and demons, and to place natural phenomena on a
basis more congruent with themselves.
The problem which had been previously approached from above was now
attacked from below; theoretic effort passed from the super- to the
sub-sensible. It was felt that to construct the universe in idea it
was necessary to have some notion of its constituent parts--of what
Lucretius subsequently called the 'First Beginnings.' Abstracting
again from experience, the leaders of scientific speculation reached
at length the pregnant doctrine of atoms and molecules, the latest
developments of which were set forth with such power and clearness at
the last meeting of the British Association. Thought, no doubt, had
long hovered about this doctrine before it attained the precision and
completeness which it assumed in the mind of Democritus,[2] a
philosopher who may well for a moment arrest our attention. 'Few
great men,' says Lange, a non-materialist, in his excellent 'History
of Materialism,' to the spirit and to the letter of which I am
equally indebted, 'have been so despitefully used by history as
Democritus. In the distorted images sent down to us through
unscientific traditions there remains of him almost nothing but the
name of "the laughing philosopher," while figures of immeasurably
smaller significance spread themselves out at full length before us.'
Lange speaks of Bacon's high appreciation of Democritus--for ample
illustrations of which I am indebted to my excellent friend Mr.
Spedding, the learned editor and biographer of Bacon. It is evident,
indeed, that Bacon considered Democritus to be a man of weightier
metal than either Plato or Aristotle, though their philosophy 'was
noised and celebrated in the schools, amid the din and pomp of
professors.' It was not they, but Genseric and Attila and the
barbarians, who destroyed the atomic philosophy. 'For at a time when
all human learning had suffered shipwreck these planks of
Aristotelian and Platonic philosophy, as being of a lighter and more
inflated substance, were preserved and came down to us, while things
more solid sank and almost passed into oblivion.'
The son of a wealthy father, Democritus devoted the whole of his
inherited fortune to the culture of his mind. He travelled
everywhere; visited Athens when Socrates and Plato were there, but
quitted the city without making himself known. Indeed, the dialectic
strife in which Socrates so much delighted had no charms for
Democritus, who held that 'the man who readily contradicts and uses
many words is unfit to learn anything truly right.' He is said to
have discovered and educated Protagoras the sophist, being struck as
much by the manner in which he, being a hewer of wood, tied up his
faggots as by the sagacity of his conversation. Democritus returned
poor from his travels, was supported by his brother, and at length
wrote his great work entitled 'Diakosmos,' which he read publicly
before the people of his native town. He was honoured by his
countrymen in various ways, and died serenely at a great age.
The principles enunciated by Democritus reveal his uncompromising
antagonism to those who deduced the phenomena of nature from the
caprices of the gods. They are briefly these:--1. From nothing comes
nothing. Nothing that exists can be destroyed. All changes are due
to the combination and separation of molecules. 2. Nothing happens
by chance. Every occurrence has its cause from which it follows by
necessity. 3. The only existing things are the atoms and empty
space; all else is mere opinion. 4. The atoms are infinite in number
and infinitely various in form; they strike together, and the lateral
motions and whirlings which thus arise are the beginnings of worlds.
5. The varieties of all things depend upon the varieties of their
atoms, in number, size, and aggregation. 6. The soul consists of
fine, smooth, round atoms, like those of fire. These are the most
mobile of all. They interpenetrate the whole body, and in their
motions the phenomena of life arise. The first five propositions are
a fair general statement of the atomic philosophy, as now held. As
regards the sixth, Democritus made his fine smooth atoms do duty for
the nervous system, whose functions were then unknown. The atoms of
Democritus are individually without sensation; they combine in
obedience to mechanical laws; and not only organic forms, but the
phenomena of sensation and thought are the result of their
combination.
That great enigma, 'the exquisite adaptation of one part of an
organism to another part, and to the conditions of life,' more
especially the construction of the human body, Democritus made no
attempt to solve. Empedocles, a man of more fiery and poetic nature,
introduced the notion of love and hate among the atoms to account for
their combination and separation. Noticing this gap in the doctrine
of Democritus, he struck in with the penetrating thought, linked,
however, with some wild speculation, that it lay in the very nature
of those combinations which were suited to their ends (in other
words, in harmony with their environment) to maintain themselves,
while unfit combinations, having no proper habitat, must rapidly
disappear. Thus more than 2,000 years ago the doctrine of the
'survival of the fittest,' which in our day, not on the basis of
vague conjecture, but of positive knowledge, has been raised to such
extraordinary significance, had received at all events partial
enunciation.[3]
Epicurus,[4] said to be the son of a poor schoolmaster at Samos, is
the next dominant figure in the history of the atomic philosophy. He
mastered the writings of Democritus, heard lectures in Athens, went
back to Sarnos, and subsequently wandered through various countries.
He finally returned to Athens, where he bought a garden, and
surrounded himself by pupils, in the midst of whom he lived a pure
and serene life, and died a peaceful death. Democritus looked to the
soul as the ennobling part of man; even beauty without understanding
partook of animalism. Epicurus also rated the spirit above the body;
the pleasure of the body was that of the moment, while the spirit
could draw upon the future and the past. His philosophy was almost
identical with that of Democritus; but he never quoted either friend
or foe. One main object of Epicurus was to free the world from
superstition and the fear of death. Death he treated with
indifference. It merely robs us of sensation. As long as we are,
death is not; and when death is, we are not. Life has no more evil
for him who has made up his mind that it is no evil not to live. He
adored the gods, but not in the ordinary fashion. The idea of divine
power, properly purified, he thought an elevating one. Still he
taught, 'Not he is godless who rejects the gods of the crowd, but
rather he who accepts them.' The gods were to him eternal and
immortal beings, whose blessedness excluded every thought of care or
occupation of any kind. Nature pursues her course in accordance with
everlasting laws, the gods never interfering. They haunt
'The lucid interspace of world and world
Where never creeps a cloud or moves a wind,
Nor ever falls the least white star of snow,
Nor ever lowest roll of thunder moans,
Nor sound of human sorrow mounts to mar
Their sacred everlasting calm.'[5]
Lange considers the relation of Epicurus to the gods subjective; the
indication probably of an ethical requirement of his own nature. We
cannot read history with open eyes, or study human nature to its
depths, and fail to discern such a requirement. Man never has been,
and he never will be, satisfied with the operations and products of
the Understanding alone; hence physical science cannot cover all the
demands of his nature. But the history of the efforts made to
satisfy these demands might be broadly described as a history of
errors--the error, in great part, consisting in ascribing fixity to
that which is fluent, which varies as we vary, being gross when we
are gross, and becoming, as our capacities widen, more abstract and
sublime. On one great point the mind of Epicurus was at peace. He
neither sought nor expected, here or hereafter, any personal profit
from his relation to the gods. And it is assuredly a fact that
loftiness and serenity of thought may be promoted by conceptions
which involve no idea of profit of this kind. 'Did I not believe,'
said a great man to me once, 'that an Intelligence is at the heart of
things, my life on earth would be intolerable.' The utterer of these
words is not, in my opinion, rendered less noble but more noble by
the fact that it was the need of ethical harmony here, and not the
thought of personal profit hereafter, that prompted his observation.
There are persons, not belonging to the highest intellectual zone,
nor yet to the lowest, to whom perfect clearness of exposition
suggests want of depth. They find comfort and edification in an
abstract and learned phraseology. To some such people Epicurus, who
spared no pains to rid his style of every trace of haze and
turbidity, appeared, on this very account, superficial. He had,
however, a disciple who thought it no unworthy occupation to spend
his days and nights in the effort to reach the clearness of his
master, and to whom the Greek philosopher is mainly indebted for the
extension and perpetuation of his fame. A century and a half after
the death of Epicurus, Lucretius[6] wrote his great poem, 'On the
Nature of Things,' in which he, a Roman, developed with extraordinary
ardour the philosophy of his Greek predecessor. He wishes to win
over his friend Memnius to the school of Epicurus; and although he
has no rewards in a future life to offer, although his object appears
to be a purely negative one, he addresses his friend with the heat of
an apostle. His object, like that of his great forerunner, is the
destruction of superstition; and considering that men trembled before
every natural event as a direct monition from the gods, and that
ever-lasting torture was also in prospect, the freedom aimed at by
Lucretius might perhaps be deemed a positive good. 'This terror,' he
says, 'and darkness of mind must be dispelled, not by the rays of the
sun and glittering shafts of day, but by the aspect and the law of
nature.' He refutes the notion that anything can come out of
nothing, or that that which is once begotten can be recalled to
nothing. The first beginnings, the atoms, are indestructible, and
into them all things can be resolved at last. Bodies are partly
atoms, and partly combinations of atoms; but the atoms nothing can
quench. They are strong in solid singleness, and by their denser
combination all things can be closely packed and exhibit enduring
strength. He denies that matter is infinitely divisible. We come at
length to the atoms, without which, as an imperishable substratum,
all order in the generation and development of things would be
destroyed.
The mechanical shock of the atoms being in his view the
all-sufficient cause of things, he combats the notion that the
constitution of nature has been in any way determined by intelligent
design. The inter-action of the atoms throughout infinite time
rendered all manner of combinations possible. Of these the fit ones
persisted, while the unfit ones disappeared. Not after sage
deliberation did the atoms station themselves in their right places,
nor did they bargain what motions they should assume. From all
eternity they have been driven together, and after trying motions and
unions of every kind, they fell at length into the arrangements out
of which this system of things has been formed. 'If you will
apprehend and keep in mind these things, nature, free at once, and
rid of her haughty lords, is seen to do all things spontaneously of
herself, without the meddling of the gods.'[7]
To meet the objection that his atoms cannot be seen, Lucretius
describes a violent storm, and shows that the invisible particles of
air act in the same way as the visible particles of water. We
perceive, moreover, the different smells of things, yet never see
them coming to our nostrils. Again, clothes hung up on a shore which
waves break upon become moist, and then get dry if spread out in the
sun, though no eye can see either the approach or the escape of the
water particles. A ring, worn long on the finger, becomes thinner; a
water-drop hollows out a stone; the ploughshare is rubbed away in the
field; the street pavement is worn by the feet; but the particles
that disappear at any moment we cannot see. Nature acts through
invisible particles. That Lucretius had a strong scientific
imagination the foregoing references prove. A fine illustration of
his power in this respect is his explanation of the apparent rest of
bodies whose atoms are in motion. He employs the image of a flock of
sheep with skipping lambs, which, seen from a distance, presents
simply a white patch upon the green hill, the jumping of the
individual lambs being quite invisible.
His vaguely-grand conception of the atoms falling eternally through
space suggested the nebular hypothesis to Kant, its first propounder.
Far beyond the limits of our visible world are to be found atoms
innumerable, which have never been united to form bodies, or which,
if once united, have been again dispersed, falling silently through
immeasurable intervals of time and space. As everywhere throughout
the All the same conditions are repeated, so must the phenomena be
repeated also. Above us, below us, beside us, therefore, are worlds
without end; and this, when considered, must dissipate every thought
of a deflection of the universe by the gods. The worlds come and go,
attracting new atoms out of limitless space, or dispersing their own
particles. The reputed death of Lucretius, which forms the basis of
Mr. Tennyson's noble poem, is in strict accordance with his
philosophy, which was severe and pure.
During the centuries lying between the first of these three
philosophers and the last, the human intellect was active in other
fields than theirs. The sophists had run through their career. At
Athens had appeared Socrates, Plato, and Aristotle, who ruined the
sophists, and whose yoke remains to some extent unbroken to the
present hour. Within this period also the School of Alexandria was
founded, Euclid wrote his 'Elements,' and made some advance in
optics. Archimedes had propounded the theory of the lever and the
principles of hydrostatics. Pythagoras had made his experiments on
the harmonic intervals, while astronomy was immensely enriched by the
discoveries of Hipparchus, who was followed by the historically more
celebrated Ptolemy. Anatomy had been made the basis of Scientific
medicine; and it is said by Draper[8] that vivisection then began.
In fact, the science of ancient Greece had already cleared the world
of the fantastic images of divinities operating capriciously through
natural phenomena. It had shaken itself free from that fruitless
scrutiny 'by the internal light of the mind alone,' which had vainly
sought to transcend experience and reach a knowledge of ultimate
causes. Instead of accidental observation, it had introduced
observation with a purpose; instruments were employed to aid the
senses; and scientific method was rendered in a great measure
complete by the union of Induction and Experiment.
What, then, stopped its victorious advance? Why was the scientific
intellect compelled, like an exhausted soil, to lie fallow for nearly
two millenniums before it could regather the elements necessary to
its fertility and strength? Bacon has already let us know one cause;
Whewell ascribes this stationary period to four causes--obscurity of
thought, servility, intolerance of disposition, enthusiasm of
temper--and he gives striking examples of each.[9] But these
characteristics must have had their antecedents in the circumstances
of the time. Rome and the other cities of the Empire had fallen into
moral putrefaction. Christianity had appeared, offering the gospel
to the poor, and, by moderation if not asceticism of life,
practically protesting against the profligacy of the age. The
sufferings of the early Christians, and the extraordinary exaltation
of mind which enabled them to triumph over the diabolical tortures to
which they were subjected,[10] must have left traces not easily
effaced. They scorned the earth, in view of that 'building of God,
that house not made with hands, eternal in the heavens.' The
Scriptures which ministered to their spiritual needs were also the
measure of their Science. When, for example, the celebrated question
of antipodes came to be discussed, the Bible was with many the
ultimate court of appeal. Augustin, who flourished A.D. 400, would
not deny the rotundity of the earth; but he would deny the possible
existence of inhabitants at the other side, 'because no such race is
recorded in Scripture among the descendants of Adam.' Archbishop
Boniface was shocked at the assumption of a 'world of human beings
out of the reach of the means of salvation.' Thus reined in, Science
was not likely to make much progress. Later on the political and
theological strife between the Church and civil governments, so
powerfully depicted by Draper, must have done much to stifle
investigation.
Whewell makes many wise and brave remarks regarding the spirit of the
Middle Ages. It was a menial spirit. The seekers after natural
knowledge had forsaken that fountain of living waters, the direct
appeal to nature by observation and experiment, and had given
themselves up to the remanipulation of the notions of their
predecessors. It was a time when thought had become abject, and when
the acceptance of mere authority led, as it always does in science,
to intellectual death. Natural events, instead of being traced to
physical, were referred to moral causes; while an exercise of the
phantasy, almost as degrading as the spiritualism of the present day,
took the place of scientific speculation. Then came the mysticism of
the Middle Ages, Magic, Alchemy, the Neo-platonic philosophy, with
its visionary though sublime abstractions, which caused men to look
with shame upon their own bodies as hindrances to the absorption of
the creature in the blessedness of the Creator. Finally came the
Scholastic philosophy, a fusion, according to Lange, of the
least-mature notions of Aristotle with the Christianity of the West.
Intellectual immobility was the result. As a traveller without a
compass in a fog may wander long, imagining he is making way, and
find himself after hours of toil at his starting-point, so the
schoolmen, having 'tied and untied the same knots and formed and
dissipated the same clouds,' found themselves at the end of centuries
in their old position.
With regard to the influence wielded by Aristotle in the Middle Ages,
and which, though to a less extent, he still wields, I would ask
permission to make one remark. When the human mind has achieved
greatness and given evidence of extraordinary power in any domain,
there is a tendency to credit it with similar power in all other
domains. Thus theologians have found comfort and assurance in the
thought that Newton dealt with the question of revelation, forgetful
of the fact that the very devotion of his powers, through all the
best years of his life, to a totally different class of ideas, not to
speak of any natural disqualification, tended to render him less
instead of more competent to deal with theological and historic
questions. Goethe, starting from his established greatness as a
poet, and indeed from his positive discoveries in Natural History,
produced a profound impression among the painters of Germany when he
published his 'Farbenlehre,' in which he endeavoured to overthrow
Newton's theory of colours. This theory he deemed so obviously
absurd that he considered its author a charlatan, and attacked him
with a corresponding vehemence of language. In the domain of Natural
History Goethe had made really considerable discoveries; and we have
high authority for assuming that, had he devoted himself wholly to
that side of science, he might have reached in it an eminence
comparable with that which he attained as a poet. In sharpness of
observation, in the detection of analogies, however apparently
remote, in the classification and organization of facts according to
the analogies discerned, Goethe possessed extraordinary powers.
These elements of scientific inquiry fall in with the discipline of
the poet. But, on the other hand, a mind thus richly endowed in the
direction of natural history may be almost shorn of endowment as
regards the more strictly called physical and mechanical sciences.
Goethe was in this condition. He could not formulate distinct
mechanical conceptions; he could not see the force of mechanical
reasoning; and in regions where such reasoning reigns supreme he
became a mere _ignis fatuus_ to those who followed him.
I have sometimes permitted myself to compare Aristotle with Goethe,
to credit the Stagirite with an almost superhuman power of amassing
and systematizing facts, but to consider him fatally defective on
that side of the mind in respect to which incompleteness has been
just ascribed to Goethe. Whewell refers the errors of Aristotle, not
to a neglect of facts, but to 'a neglect of the idea appropriate to
the facts; the idea of Mechanical cause, which is Force, and the
substitution of vague or inapplicable notions, involving only
relations of space or emotions of wonder.' This is doubtless true;
but the word 'neglect' implies mere intellectual misdirection,
whereas in Aristotle, as in Goethe, it was not, I believe,
misdirection, but sheer natural incapacity which lay at the root of
his mistakes. As a physicist, Aristotle displayed what we should
consider some of the worst attributes of a modern physical
investigator--indistinctness of ideas, confusion of mind, and a
confident use of language, which led to the delusive notion that he
had really mastered his subject, while he had as yet failed to grasp
even the elements of it. He put words in the place of things,
subject in the place of object. He preached Induction without
practising it, inverting the true order of inquiry by passing from
the general to the particular, instead of from the particular to the
general. He made of the universe a closed sphere, in the centre of
which he fixed the earth, proving from general principles, to his own
satisfaction and to that of the world for near 2,000 years, that no
other universe was possible. His notions of motion were entirely
unphysical. It was natural or unnatural, better or worse, calm or
violent--no real mechanical conception regarding it lying at the
bottom of his mind. He affirmed that a vacuum could not exist, and
proved that if it did exist motion in it would be impossible. He
determined _à priori_ how many species of animals must exist, and
shows on general principles why animals must have such and such
parts. When an eminent contemporary philosopher, who is far removed
from errors of this kind, remembers these abuses of the _à priori_
method, he will be able to make allowance for the jealousy of
physicists as to the acceptance of so-called _à priori_ truths.
Aristotle's errors of detail, as shown by Eucken and Lange, were
grave and numerous. He affirmed that only in man we had the beating
of the heart, that the left side of the body was colder than the
right, that men have more teeth than women, and that there is an
empty space at the back of every man's head.
There is one essential quality in physical conceptions which was
entirely wanting in those of Aristotle and his followers. I wish it
could be expressed by a word untainted by its associations; it
signifies a capability of being placed as a coherent picture before
the mind. The Germans express the act of picturing by the word
_vorstellen_, and the picture they call a _Vorstellung_. We have no
word in English which comes nearer to our requirements than
_Imagination_, and, taken with its proper limitations, the word
answers very well; but, as just intimated, it is tainted by its
associations, and therefore objectionable to some minds. Compare,
with reference to this capacity of mental presentation, the case of
the Aristotelian who refers the ascent of water in a pump to Nature's
abhorrence of a vacuum, with that of Pascal when he proposed to solve
the question of atmospheric pressure by the ascent of the Puy de
Dome. In the one case the terms of the explanation refuse to fall
into place as a physical image; in the other the image is distinct,
the fall and rise of the barometer being clearly figured as the
balancing of two varying and opposing pressures.
During the drought of the Middle Ages in Christendom, the Arabian
intellect, as forcibly shown by Draper, was active. With the
intrusion of the Moors into Spain, he says, order, learning, and
refinement took the place of their opposites. When smitten with
disease, the Christian peasant resorted to a shrine, the Moorish one
to an instructed physician. The Arabs encouraged translations from
the Greek philosophers, but not from the Greek poets. They turned in
disgust 'from the lewdness of our classical mythology, and denounced
as an unpardonable blasphemy all connexion between the impure
Olympian Jove and the Most High God.' Draper traces still further
than Whewell the Arab elements in our scientific terms, and points
out that the under garment of ladies retains to this hour its Arab
name. He gives examples of what Arabian men of science accomplished,
dwelling particularly on Alhazen, who was the first to correct the
Platonic notion that rays of light are emitted by the eye. He
discovered atmospheric refraction, and points out that we see the sun
and the moon after they have set. He explains the enlargement of the
sun and moon, and the shortening of the vertical diameters of both
these bodies, when near the horizon. He is aware that the atmosphere
decreases in density with increase of elevation, and actually fixes
its height at 58½ miles. In the Book of the Balance Wisdom, he sets
forth the connexion between the weight of the atmosphere and its
increasing density. He shows that a body will weigh differently in a
rare and dense atmosphere: he considers the force with which plunged
bodies rise through heavier media. He understands the doctrine of
the centre of gravity, and applies it to the investigation of
balances and steelyards. He recognises gravity as a force, though he
falls into the error of making it diminish simply as the distance
increased, and of making it purely terrestrial. He knows the
relation between the velocities, spaces, and times of falling bodies,
and has distinct ideas of capillary attraction. He improved the
hydrometer. The determination of the densities of bodies as given by
Alhazen approach very closely to our own. 'I join,' says Draper, in
the pious prayer of Alhazen, 'that in the day of judgment the
All-Merciful will take pity on the soul of Abur-Raihân, because he
was the first of the race of men to construct a table of specific
gravities.' If all this be historic truth (and I have entire
confidence in Dr. Draper), well may he 'deplore the systematic manner
in which the literature of Europe has contrived to put out of sight
our scientific obligations to the Mahommedans.'[11]
The strain upon the mind during the stationary period towards
ultra-terrestrial things, to the neglect of problems close at hand,
was sure to provoke reaction. But the reaction was gradual; for the
ground was dangerous, a power being at hand competent to crush the
critic who went too far. To elude this power and still allow
opportunity for the expression of opinion, the doctrine of 'twofold
truth' was invented, according to which an opinion might be held;
'theologically' and the opposite opinion 'philosophically.'[12] Thus
in the thirteenth century the creation of the world in six days, and
the unchangeableness of the individual soul which had been so
distinctly affirmed by St. Thomas Aquinas, were both denied
philosophically, but admitted to be true as articles of the Catholic
faith. When Protagoras uttered the maxim which brought upon him so
much vituperation, that' opposite assertions are equally true,' he
simply meant that human beings differed so much from each other that
what was subjectively true to the one might be subjectively untrue to
the other. The great Sophist never meant to play fast and loose with
the truth by saying that one of two opposite assertions, made by the
same individual, could possibly escape being a lie. It was not
'sophistry,' but the dread of theologic vengeance that generated this
double dealing with conviction; and it is astonishing to notice what
lengths were possible to men who were adroit in the use of artifices
of this kind.
Towards the close of the stationary period a word-weariness, if I may
so express it, took more and more possession of men's minds.
Christendom had become sick of the School philosophy and its verbal
wastes, which led to no issue, but left the intellect in everlasting
haze. Here and there was heard the voice of one impatiently crying
in the wilderness, 'Not unto Aristotle, not unto subtle hypothesis,
not unto church, Bible, or blind tradition, must we turn for a
knowledge of the universe, but to the direct investigation of Nature
by observation and experiment.' In 1543 the epoch-making work of
Copernicus on the paths of the heavenly bodies appeared. The total
crash of Aristotle's closed universe with the earth at its centre
followed as a consequence, and 'the earth moves!' became a kind of
watchword among intellectual freemen. Copernicus was Canon of the
Church of Frauenburg, in the diocese of Ermeland. For
three-and-thirty years he had withdrawn himself from the world and
devoted himself to the consolidation of his great scheme of the solar
system. He made its blocks eternal; and even to those who feared it
and desired its overthrow it was so obviously strong that they
refrained for a time from meddling with it. In the last year of the
life of Copernicus his book appeared: it is said that the old man
received a copy of it a few days before his death, and then departed
in peace.
The Italian philosopher Giordano Bruno was one of the earliest
converts to the new astronomy. Taking Lucretius as his exemplar, he
revived the notion of the infinity of worlds; and, combining with it
the doctrine of Copernicus, reached the sublime generalization that
the fixed stars are suns, scattered numberless through space and
accompanied by satellites, which bear the same relation to them, that
our earth does to our sun, or our moon to our earth. This was an
expansion of transcendent import; but Bruno came closer than this to
our present line of thought. Struck with the problem of the
generation and maintenance of organisms, and duly pondering it, he
came to the conclusion that Nature in her productions does not
imitate the technic of man. Her process is one of unravelling and
unfolding. The infinity of forms under which matter appears were not
imposed upon it by an external artificer; by its own intrinsic force
and virtue it brings these forms forth. Matter is not the mere
naked, empty capacity which philosophers have pictured her to be, but
the universal mother who brings forth all things as the fruit of her
own womb.
This outspoken man was originally a Dominican monk. He was accused
of heresy and had to fly, seeking refuge in Geneva, Paris, England,
and Germany. In 1592 he fell into the hands of the Inquisition at
Venice. He was imprisoned for many years, tried, degraded,
excommunicated, and handed over to the civil power, with the request
that he should be treated gently and 'without the shedding of blood.'
This meant that he was to be burnt; and burnt accordingly he was, on
the 16th of February, 1600. To escape a similar fate Galileo,
thirty-three years afterwards, abjured, upon his knees, and with his
hand upon the holy gospels, the heliocentric doctrine which he knew
to be true. After Galileo came Kepler, who from his German home
defied the power beyond the Alps. He traced out from pre-existing
observations the laws of planetary motion. Materials were thus
prepared for Newton, who bound those empirical laws together by the
principle of gravitation.
In the seventeenth century Bacon and Descartes, the restorers of
philosophy, appeared in succession. Differently educated and
endowed, their philosophic tendencies were different. Bacon held
fast to Induction, believing firmly in the existence of an external
world, and making collected experiences the basis of all knowledge.
The mathematical studies of Descartes gave him a bias towards
Deduction; and his fundamental principle was much the same as that of
Protagoras, who made the individual man the measure of all things.
'I think, therefore I am,' said Descartes. Only his own identity was
sure to him; and the development of this system would have led to an
idealism in which the outer world would be resolved into a mere
phenomenon of consciousness. Gassendi, one of Descartes's
contemporaries, of whom we shall hear more presently, quickly pointed
out that the fact of personal existence would be proved as well by
reference to any other act as to the act of thinking. I eat,
therefore I am; or I love, therefore I am, would be quite as
conclusive. Lichtenberg showed that the very thing to be proved was
inevitably postulated in the first two words, 'I think;' and that no
inference from the postulate could by any possibility be stronger
than the postulate itself.
But Descartes deviated strangely from the idealism implied in his
fundamental principle. He was the first to reduce, in a manner
eminently capable of bearing the test of mental presentation, vital
phenomena to purely mechanical principles. Through fear or love,
Descartes was a good churchman; he accordingly rejects the notion of
an atom, because it was absurd to suppose that God, if he so pleased,
could not divide an atom; he puts in the place of the atoms small
round particles and light splinters, out of which he builds the
organism. He sketches with marvellous physical insight a machine,
with water for its motive power, which shall illustrate vital
actions. He has made clear to his mind that such a machine would be
competent to carry on the processes of digestion, nutrition, growth,
respiration, and the beating of the heart. It would be competent to
accept impressions from the external sense, to store them up in
imagination and memory, to go through the internal movements of the
appetites and passions, the external movement of limbs. He deduces
these functions of his machine from the mere arrangement of its
organs, as the movement of a clock or other automaton is deduced from
its weights and wheels. 'As far as these functions are concerned,'
he says, 'it is not necessary to conceive any other vegetative or
sensitive soul, nor any other principle of motion or of life, than
the blood and the spirits agitated by the fire which burns
continually in the heart, and which is in no wise different from the
fires which exist in inanimate bodies.' Had Descartes been
acquainted with the steam-engine, he would have taken it, instead of
a fall of water, as his motive power, and shown the perfect analogy
which exists between the oxidation of the food in the body and that
of the coal in the furnace. He would assuredly have anticipated
Mayer in calling the blood which the heart diffuses 'the oil of the
lamp of life;' deducing all animal motions from the combustion of
this oil, as the motions of a steam-engine are deduced from the
combustion of its coal. As the matter stands, however, and
considering the circumstances of the time, the boldness, clearness,
and precision with which he grasped the problem of vital dynamics
constitute a marvellous illustration of intellectual power.[13]
During the Middle Ages the doctrine of atoms had to all appearance
vanished from discussion. In all probability it held its ground
among sober-minded and thoughtful men, though neither the church nor
the world was prepared to hear of it with tolerance. Once, in the
year 1348, it received distinct expression. But retractation by
compulsion immediately followed, and, thus discouraged, it slumbered
till the seventeenth century, when it was revived by a contemporary
and friend of Hobbes and Malmesbury, the orthodox Catholic provost of
Digne, Gassendi. But before stating his relation to the Epicurean
doctrine, it will be well to say a few words on the effect, as
regards science, of the general introduction of monotheism among
European nations.
'Were men,' says Hume, 'led into the apprehension of invisible
intelligent power by 'contemplation of the works of Nature, they
could never possibly entertain any conception but of one single
being, who bestowed existence and order on this vast machine, and
adjusted all its parts to one regular system.' Referring to the
condition of the heathen, who sees a god behind every natural event,
thus peopling the world with thousands of beings whose caprices are
incalculable, Lange shows the impossibility of any compromise between
such notions and those of science, which proceeds on the assumption
of never-changing law and causality. 'But,' he continues, with
characteristic penetration, 'when the great thought of one God,
acting as a unit upon the universe, has been seized, the connexion of
things in accordance with the law of cause and effect is not only
thinkable, but it is a necessary consequence of the assumption. For
when I see ten thousand wheels in motion, and know, or believe, that
they are all driven by one, then I know that I have before me a
mechanism the action of every part of which is determined by the plan
of the whole. So much being assumed, it follows that I may
investigate the structure of that machine, and the various motions of
its parts. For the time being, therefore, this conception renders
scientific action free.' In other words, were a capricious God at
the circumference of every wheel and at the end of every lever, the
action of the machine would be incalculable by the methods of
science. But the action of all its parts being rigidly determined by
their connexions and relations, and these being brought into play by
a single self-acting driving wheel, then, though this last prime
mover may elude me, I am still able to comprehend the machinery which
it sets in motion. We have here a conception of the relation of
Nature to its Author which seems perfectly acceptable to some minds,
but perfectly intolerable to others. Newton and Boyle lived and
worked happily under the influence of this conception; Goethe
rejected it with vehemence, and the same repugnance to accepting it
is manifest in Carlyle.[14]
The analytic and synthetic tendencies of the human mind exhibit
themselves throughout history, great writers ranging themselves
sometimes on the one side, sometimes on the other. Men of warm
feelings and minds open to the elevating impressions produced by
Nature as a whole, whose satisfaction, therefore, is rather ethical
than logical, lean to the synthetic side; while the analytic
harmonizes best with the more precise and more mechanical bias which
seeks the satisfaction of the understanding. Some form of pantheism
was usually adopted by the one, while a detached Creator, working
more or less after the manner of men, was often assumed by the other.
Gassendi is hardly to be ranked with either. Having formally
acknowledged God as the great first cause, he immediately dropped the
idea, applied the known laws of mechanics to the atoms, deducing
thence all vital phenomena. He defended Epicurus, and dwelt upon his
purity, both of doctrine and of life. True he was a heathen, but so
was Aristotle. He assailed superstition and religion, and rightly,
because he did not know the true religion. He thought that the gods
neither rewarded nor punished, and adored them purely in consequence
of their completeness; here we see, says Gassendi, the reverence of
the child instead of the fear of the slave. The errors of Epicurus
shall be corrected, the body of his truth retained; and then Gassendi
proceeds, as any heathen might do, to build up the world, and all
that therein is, of atoms and molecules. God, who created earth and
water, plants and animals, produced in the first place a definite
number of atoms, which constituted the seed of all things. Then
began that series of combinations and decompositions which goes on at
present, and which will continue in future. The principle of every
change resides in matter. In artificial productions the moving
principle is different from the material worked upon; but in Nature
the agent works within, being the most active and mobile part of the
material itself. Thus, this bold ecclesiastic, without incurring the
censure of the church or the world, contrives to outstrip Mr. Darwin.
The same cast of mind which caused him to detach the Creator from his
universe led him also to detach the soul from the body, though to the
body he ascribes an influence so large as to render the soul almost
unnecessary. The aberrations of reason were in his view an affair of
the material brain. Mental disease is brain disease; but then the
immortal reason sits apart, and cannot be touched by the disease.
The errors of madness are errors of the instrument, not of the
performer.
It may be more than a mere result of education, connecting itself
probably with the deeper mental structure of the two men, that the
idea of Gassendi above enunciated is substantially the same as that
expressed by Professor Clerk Maxwell at the close of the very able
lecture delivered by him at Bradford last year. According to both
philosophers, the atoms, if I understand aright, are the prepared
materials which, formed by the skill of the highest, produce by their
subsequent inter-action all the phenomena of the material world.
There seems to be this difference, however, between Gassendi and
Maxwell. The one _postulates_, the other _infers_ his first cause.
In his 'manufactured articles,' as he calls the atoms, Professor
Maxwell finds the basis of an induction which enables him to scale
philosophic heights considered inaccessible by Kant, and to take the
logical step from the atoms to their Maker.
Accepting here the leadership of Kant, I doubt the legitimacy of
Maxwell's logic; but it is impossible not to feel the ethic glow with
which his lecture concludes. There is, moreover, a very noble strain
of eloquence in his description of the steadfastness of the
atoms:--'Natural causes, as we know, are at work, which tend to
modify, if they do not at length destroy, all the arrangements and
dimensions of the earth and the whole solar system. But though in
the course of ages catastrophes have occurred and may yet occur in
the heavens, though ancient systems may be dissolved and new systems
evolved out of their ruins, the molecules out of which these systems
are built--the foundation stones of the material universe--remain
unbroken and unworn.'
The atomic doctrine, in whole or in part, was entertained by Bacon,
Descartes, Hobbes, Locke, Newton, Boyle, and their successors, until
the chemical law of multiple proportions enabled Dalton to confer
upon it an entirely new significance. In our day there are
secessions from the theory, but it still stands firm. Loschmidt,
Stoney, and Sir William Thomson have sought to determine the sizes of
the atoms, or rather to fix the limits between which their sizes lie;
while only last year the discourses of Williamson and Maxwell
illustrate the present hold of the doctrine upon the foremost
scientific minds. In fact, it may be doubted whether, wanting this
fundamental conception, a theory of the material universe is capable
of scientific statement.
Ninety years subsequent to Gassendi the doctrine of bodily
instruments, as it may be called, assumed immense importance in the
hands of Bishop Butler, who, in his famous 'Analogy of Religion,'
developed, from his own point of view, and with consummate sagacity,
a similar idea. The Bishop still influences superior minds; and it
will repay us to dwell for a moment on his views. He draws the
sharpest distinction between our real selves and our bodily
instruments. He does not, as far as I remember, use the word soul,
possibly because the term was so hackneyed in his day as it had been
for many generations previously. But he speaks of 'living powers,'
'perceiving' or 'percipient powers,' 'moving agents,' 'ourselves,' in
the same sense as we should employ the term soul. He dwells upon the
fact that limbs may be removed, and mortal diseases assail the body,
the mind, almost up to the moment of death, remaining clear. He
refers to sleep and to swoon, where the 'living powers' are suspended
but not destroyed. He considers it quite as easy to conceive of
existence out of our bodies as in them: that we may animate a
succession of bodies, the dissolution of all of them having no more
tendency to dissolve our real selves, or 'deprive us of living
faculties--the faculties of perception and action--than the
dissolution of any foreign matter which we are capable of receiving
impressions from, or making use of for the common occasions of life.'
This is the key of the Bishop's position; 'our organized bodies are
no more a part of ourselves than any other matter around us.' In
proof of this he calls attention to the use of glasses, which
'prepare objects' for the 'percipient power' exactly as the eye does.
The eye itself is no more percipient than the glass; is quite as much
the instrument of the true self, and also as foreign to the true
self, as the glass is. 'And if we see with our eyes only in the same
manner as we do with glasses, the like may justly be concluded from
analogy of all our senses.'
Lucretius, as you are aware, reached a precisely opposite conclusion;
and it certainly would be interesting, if not profitable, to us all,
to hear what he would or could urge in opposition to the reasoning of
the Bishop. As a brief discussion of the point will enable us to see
the bearings of an important question, I will here permit a disciple
of Lucretius to try the strength of the Bishop's position, and then
allow the Bishop to retaliate, with the view of rolling back, if he
can, the difficulty upon Lucretius.