PIONEERS OF EVOLUTION FROM THALES TO HUXLEY
With an
Intermediate Chapter on the Causes of Arrest of the
Movement
by
EDWARD CLODD
President of the Folk-Lore
Society Author of the Childhood of the World, The Story of
Creation, The Story of Primitive Man, etc.
With
Portraits
New York D. Appleton and
Company 1897
Copyright, 1897, by D. Appleton and
Company.
To MY BELOVED
A. A. L.
WHOSE
FELLOWSHIP AND HELP
HAVE SWEETENED
LIFE.
PREFACE.
This book needs only brief
introduction. It attempts to tell the story of the origin of the Evolution
idea in Ionia, and, after long arrest, of the revival of that idea in modern
times, when its profound and permanent influence on thought in all
directions, and, therefore, on human relations and conduct, is
apparent.
Between birth and revival there were the centuries of
suspended animation, when the nepenthe of dogma drugged the reason; the
Church teaching, and the laity mechanically accepting, the sufficiency of
the Scriptures and of the General Councils to decide on matters which
lie outside the domain of both. Hence the necessity for particularizing
the causes which actively arrested advance in knowledge for sixteen
hundred years.
In indicating the parts severally played in the
Renascence of Evolution by a small group of illustrious men, the writer,
through the courtesy of Mr. Herbert Spencer, has been permitted to see the
original documents which show that the theory of Evolution as a whole; i. e.,
as dealing with the non-living, as well as with the living, contents of
the Universe, was formulated by Mr. Spencer in the year preceding
the publication of the Origin of Species.
ROSEMONT, TUFNELL PARK,
LONDON, N., _14th December,
1896_.
CONTENTS.
PART
I.
PAGE PIONEERS OF EVOLUTION FROM THALES TO LUCRETIUS--B.
C. 600-A. D.
50 1
PART
II.
THE ARREST OF INQUIRY--A. D. 50-A. D. 1600.
1. FROM THE
EARLY CHRISTIAN PERIOD TO THE TIME OF AUGUSTINE--A. D. 50-A. D.
400 37
2. FROM AUGUSTINE TO LORD BACON--A. D.
400-A. D. 1600 73
PART III.
THE
RENASCENCE OF SCIENCE--A. D. 1600
ONWARD 99
PART
IV.
MODERN EVOLUTION--
1. DARWIN AND
WALLACE 126
2. HERBERT
SPENCER 175
3. THOMAS HENRY
HUXLEY
201
INDEX 267
"Nature,
which governs the whole, will soon change all things which thou seest, and
out of their substance will make other things, and again other things from
the substance of them, in order that the world may be ever
new." _Marcus Aurelius_, vii,
25.
PIONEERS OF EVOLUTION.
_PART
I._
PIONEERS OF EVOLUTION FROM THALES TO LUCRETIUS.
B. C. 600-A.
D. 50.
"These all died in faith, not having received the promises,
but having seen them afar off, and were persuaded of
them."--HEBREWS xi. 13.
"One event is always the son of
another, and we must never forget the parentage," said a Bechuana chief to
Casalis the missionary. The barbarian philosopher spoke wiser than he knew,
for in his words lay that doctrine of continuity and unity which is the creed
of modern science. They are a suitable text to the discourse of this chapter,
the design of which is to bring out what the brilliancy of
present-day discoveries tends to throw into shadow, namely, the antiquity of
the ideas of which those discoveries are the result. Although the Theory
of Evolution, as we define it, is new, the speculations which made
it possible are, at least, twenty-five centuries old. Indeed, it is
not practicable, since the remote past yields no documents, to fix
their beginnings. Moreover, charged, as they are, with many crudities,
they are not detachable from the barbaric conceptions of the Universe
which are the philosophies of past, and the legends of present,
times.
Fontenelle, a writer of the last century, shrewdly remarked that
"all nations made the astounding part of their myths while they were
savage, and retained them from custom and religious conservatism." For,
as Walter Bagehot argues in his brilliant little book on Physics
and Politics, and as all anthropological research goes to prove, the
lower races are non-progressive both through fear and instinct. And
the majority of the members of higher races have not escaped from
the operation of the same causes. Hence the persistence of coarse
and grotesque elements in speculations wherein man has made gradual
approach to the truth of things; hence, too--the like phenomena having to
be interpreted--the similarity of the explanation of them. And as
primitive myth embodies primitive theology, primitive morals, and
primitive science, the history of beliefs shows how few there be who have
escaped from the tyranny of that authority and sanctity with which the lapse
of time invests old ideas.
Dissatisfaction is a necessary condition of
progress; and dissatisfaction involves opposition. As Grant Allen puts it, in
one of his most felicitous poems:
If systems that be are the order
of God, Revolt is a part of the order.
Hence a stage in the
history of certain peoples when, in questioning what is commonly accepted,
intellectual freedom is born. Such a stage was markedly reached whenever, for
example, an individual here and there challenged the current belief about the
beginnings and nature of things, beliefs held because they were taught, not
because their correspondence with fact had been examined.
A pioneer
(French, _pionnier_; Italian, _pedone_; from Latin _pedes_) is, literally, a
foot-soldier; one who goes before an army to clear the road of obstructions.
Hence the application of the term to men who are in the van of any new
movement; hence its special fitness in the present connection, as designating
men whose speculations cut a pathway through jungles of myth and legend to
the realities of things. The Pioneers of Evolution--the first on record to
doubt the truth of the theory of special creation, whether as the work of
departmental gods or of one Supreme Deity, matters not--lived in Greece about
the time already mentioned; six centuries before Christ. Not in the early
stages of the Evolution idea, in the Greece limited, as now, to a rugged
peninsula in the southeastern corner of Europe and to the surrounding
islands, but in the Greece which then included Ionia, on the opposite
seaboard of Asia Minor.
From times beyond memory or record, the
islands of the Ægean had been the nurseries of culture and adventure. Thence
the maritime inhabitants had spread themselves both east and west, feeding
the spirit of inquiry, and imbibing influences from older civilizations,
notably of Egypt and Chaldæa. But, mix as they might with other peoples, the
Greeks never lost their own strongly marked individuality, and, in imparting
what they had acquired or discovered to younger peoples, that is, younger
in culture, they stamped it with an impress all their own.
At the
later period with which we are dealing, refugees from the Peloponnesus, who
would not submit to the Dorian yoke, had been long settled in Ionia. To what
extent they had been influenced by contact with their neighbours is a
question which, even were it easy to answer, need not occupy us here. Certain
it is that trade and travel had widened their intellectual horizon, and
although India lay too remote to touch them closely (if that incurious,
dreamy East had touched them, it would have taught them nothing), there was
Babylonia with her star-watchers, and Egypt with her land-surveyors. From the
one, these Ionians probably gained knowledge of certain periodic movements of
some of the heavenly bodies; and from the other, a few rules of mensuration,
perchance a little crude science. But this is conjecture. For all the rest
that she evolved, and with which she enriched the world, ancient Greece is
in debt to none.
While the Oriental shrunk from quest after causes,
looking, as Professor Butcher aptly remarks in his Aspects of the Greek
Genius, on "each fresh gain of earth as so much robbery of heaven," the Greek
eagerly sought for the law governing the facts around him. And in Ionia was
born the idea foreign to the East, but which has become the starting-point of
all subsequent scientific inquiry--the idea that Nature works by fixed
laws. Sir Henry Maine said that "except the blind forces of Nature,
nothing moves which is not Greek in its origin," and we feel how hard it is
to avoid exaggeration when speaking of the heritage bequeathed by Greece
as the giver of every fruitful, quickening idea which has developed
human faculty on all sides, and enriched every province of life.
Amid serious defects of character, as craftiness, avariciousness,
and unscrupulousness, the Greeks had the redeeming grace of pursuit
after knowledge which naught could baffle (Plato, Republic, vol. iv, p.
435), and that healthy outlook on things which saved them from
morbid introspection. There arose among them no Simeon Stylites to
mount his profitless pillar; no filth-ingrained fakir to waste life
in contemplating the tip of his nose; no schoolman to idly speculate
how many angels could dance upon a needle's point; or to debate such
fatuous questions as the language which the saints in heaven will speak
after the Last Judgment.
In his excellent and cautious survey of Early
Greek Philosophy, which we mainly follow in this section, Professor Burnet
says that the real advance made by the Ionians was through their "leaving off
telling tales. They gave up the hopeless task of describing what was when as
yet there was nothing, and asked instead what all things really are
now." For the early notions of the Greeks about nature, being an
inheritance from their barbaric ancestors, were embodied in myths and
legends bearing strong resemblance to those found among the uncivilized
tribes of Polynesia and elsewhere in our day. For example, the old
nature-myth of Cronus separating heaven and earth by the mutilation of Uranus
occurs among Chinese, Japanese, and Maoris, and among the ancient Hindus
and Egyptians.
The earliest school of scientific speculation was at
Miletus, the most flourishing city of Ionia. Thales, whose name heads the
list of the "Seven Sages," was its founder. As with other noted philosophers
of this and later periods, neither the exact date of his birth nor of his
death are known, but the sixth century before Christ may be held to cover
the period when he "flourished."
That "nothing comes into being out of
nothing, and that nothing passes away into nothing," was the conviction with
which he and those who followed him started on their quest. All around was
change; everything always becoming something else; "all in motion like
streams." There must be that which is the vehicle of all the changes, and of
all the motions which produce them. _What_, therefore, was this permanent and
primary substance? in other words, of what is the world made? And
Thales, perhaps through observing that it could become vaporous,
liquid, and solid in turn; perhaps--if, as tradition records, he
visited Egypt--through watching the wonder-working, life-giving Nile; perhaps
as doubtless sharing the current belief in an ocean-washed earth, said
that the primary substance was WATER. Anaximander, his friend and
pupil, disagreeing with what seemed to him a too concrete answer, argued,
in more abstract fashion, that "the material cause and first element
of things was the Infinite." This material cause, which he was the
first thus to name, "is neither water nor any other of what are now called
the _elements_" (we quote from Theophrastus, the famous pupil of
Aristotle, born at Eresus in Lesbos, 371 B. C.). Perhaps, following
Professor Burnet's able guidance through the complexities of definitions, the
term BOUNDLESS best expresses the "one eternal, indestructible substance
out of which everything arises, and into which everything once
more returns"; in other words, the exhaustless stock of matter from which
the waste of existence is being continually made good.
Anaximander was
the first to assert the origin of life from the non-living, i. e., "the moist
element as it was evaporated by the sun," and to speak of man as "like
another animal, namely, a fish, in the beginning." This looks well-nigh akin
to prevision of the mutability of species, and of what modern biology has
proved concerning the marine ancestry of the highest animals, although it is
one of many ancient speculations as to the origin of life in slimy matter.
And when Anaximander adds that "while other animals quickly find food
for themselves, man alone requires a prolonged period of suckling,"
he anticipates the modern explanation of the origin of the
rudimentary family through the development of the social instincts and
affections. The lengthening of the period of infancy involves dependence on
the parents, and evolves the sympathy which lies at the base of
social relations. (Cf. Fiske's Outlines of Cosmic Philosophy, vol. ii, pp.
344, 360.)
In dealing with speculations so remote, we have to guard
against reading modern meanings into writings produced in ages whose
limitations of knowledge were serious, and whose temper and standpoint are
wholly alien to our own. For example, shrewd as are some of the guesses made
by Anaximander, we find him describing the sun as "a ring
twenty-eight times the size of the earth, like a cartwheel with the felloe
hollow and full of fire, showing the fire at a certain point, as if through
the nozzle of a pair of bellows." And if he made some approach to
truer ideas of the earth's shape as "convex and round," the world of his
day, as in the days of Homer, thought of it as flat and as floating on
the all-surrounding water. The Ionian philosophers lacked not insight,
but the scientific method of starting with working hypotheses, or
of observation before theory, was as yet unborn.
In this brief survey
of the subject there will be no advantage in detailing the various
speculations which followed on the heels of those of Thales and Anaximander,
since these varied only in non-essentials; or, like that of Pythagoras and
his school, which Zeller regards as the outcome of the teachings of
Anaximander, were purely abstract and fanciful. As is well known, the
Pythagoreans, whose philosophy was ethical as well as cosmical, held that all
things are made of numbers, each of which they believed had its special
character and property. A belief in such symbols as entities seems impossible
to us, but its existence in early thought is conceivable when, as Aristotle
says, they were "not separated from the objects of sense." Even in the
present day, among the eccentric people who still believe in the modern
sham agnosticism, known as theosophy, and in astrology, we find the
delusion that numbers possess inherent magic or mystic virtues. So far as
the ancients are concerned, "consider," as Mr. Benn remarks in his
Greek Philosophers (vol. i, p. 12), "the lively emotions excited at a
time when multiplication and division, squaring and cubing, the rule
of three, the construction and equivalence of figures, with all
their manifold applications to industry, commerce, fine arts, and
tactics, were just as strange and wonderful as electrical phenomena are to us
... and we shall cease to wonder that a mere form of thought, a
lifeless abstraction, should once have been regarded as the solution of
every problem; the cause of all existence; or that these speculations
were more than once revived in after ages."
Xenophanes of Colophon,
one of the twelve Ionian cities of Asia Minor, deserves, however, a passing
reference. He, with Parmenides and Zeno, are the chief representatives of the
Eleatic school, so named from the city in southwestern Italy where a Greek
colony had settled. The tendency of that school was toward metaphysical
theories. He was the first known observer to detect the value of fossils as
evidences of the action of water, but his chief claim to notice rests on the
fact that, passing beyond the purely physical speculations of the Ionian
school, he denied the idea of a primary substance, and theorized about the
nature and actions of superhuman beings. Living at a time when there was
a revival of old and gross superstitions to which the vulgar had
recourse when fears of invasions arose, he dared to attack the old and
persistent ideas about the gods, as in the following sentences from the
fragments of his writings:
"Homer and Hesiod have ascribed to the gods
all things that are a shame and a disgrace among men, theft and adulteries
and deception of one another."
"There never was nor will be a man who
has clear certainty as to what I say about the gods and about all things; for
even if he does chance to say what is right, yet he himself does not know
that it is so. But all are free to guess."
"Mortals think that the
gods were born as they are, and have senses and a voice and body like their
own. So the Ethiopians make their gods black and snub-nosed; the Thracians
give theirs red hair and blue eyes."
"There is one god, the greatest
among gods and men, unlike mortals both in mind and body."
Had such
heresies been spoken in Athens, where the effects of a religious revival were
still in force, the "secular arm" of the archons would probably have made
short work of Xenophanes. But in Elea, or in whatever other colony he may
have lived, "the gods were left to take care of themselves."
Greater
than the philosophers yet named is Heraclitus of Ephesus, nicknamed "the
dark," from the obscurity of his style. His original writings have shared the
fate of most documents of antiquity, and exist, like many of these, only in
fragments preserved in the works of other authors. Many of his aphorisms are
indeed dark sayings, but those that yield their meaning are full of truth and
suggestiveness. As for example:
"The eyes are more exact witnesses
than the ears."
"You will not find out the boundaries of soul by
travelling in any direction."
"Man is kindled and put out like a light
in the nighttime."
"Man's character is his fate."
But these have
special value as keys to his philosophy:
"You cannot step twice into the
same rivers; for fresh waters are ever flowing in upon you."
"Homer
was wrong in saying: 'Would that strife might perish from among gods and
men!' He did not see that he was praying for the destruction of the universe;
for, if his prayer were heard, all things would pass away."
Flux or
movement, says Heraclitus, is the all-pervading law of things, and in the
opposition of forces, by which things are kept going, there is underlying
harmony. Still on the quest after the primary substance whose manifestations
are so various, he found it in FIRE, since "the quantity of it in a flame
burning steadily appears to remain the same; the flames seems to be what we
call a 'thing.' And yet the substance of it is continually changing. It is
always passing away in smoke, and its place is always being taken by fresh
matter from the fuel that feeds it. This is just what we want. If we regard
the world as an 'ever-living fire'--'this order, which is the same in all
things, and which no one of gods or men has made'--we can understand how fire
is always becoming all things, while all things are always returning to it."
And as is the world, so is man, made up, like it, both soul and body, of the
fire, the water, and the earth. We are and are not the same for two
consecutive moments; "the fire in us is perpetually becoming water, and the
water earth, but as the opposite process goes on simultaneously we appear
to remain the same."
As speculation advanced, it became more and more
applied to details, theories of the beginnings of life being followed by
theories of the origin of its various forms. This is a feature of the
philosophy of Empedocles, who flourished in the fifth century B. C. The
advance of Persia westward had led to migrations of Greeks to the south of
Italy and Sicily, and it was at Agrigentum, in that island, that
Empedocles was born about 490. He has an honoured place among the earliest
who supplanted _guesses_ about the world by _inquiry_ into the world
itself. Many legends are told of his magic arts, one of which, it will
be remembered, Matthew Arnold makes an occasion of some fine reflections
in his poem Empedocles in Etna. The philosopher was said to have
brought back to life a woman who apparently had been dead for thirty days. As
he ascends the mountain, Pausanias of Gela, with an address to whom
the poem of Empedocles opens, would fain have his curiosity slaked as
to this and other marvels reported of him:
Ask not the latest news
of the last miracle, Ask not what days and nights In trance
Pantheia lay, But ask how thou such sights May'st see without
dismay; Ask what most helps when known, thou son of Anchitus.
His
speculations about things, like those of Parmenides before him and of
Lucretius after him, are set down in verse. From the remains of his Poem on
Nature we learn that he conceived "the four roots of all things" to be FIRE,
AIR, EARTH, and WATER. They are "fools, lacking far-reaching thoughts, who
deem that what before was not comes into being, or that aught can perish and
be utterly destroyed." Therefore the "roots" or elements are eternal and
indestructible. They are acted upon by two forces, which are also material,
LOVE and STRIFE; the one a uniting agent, the other a disrupting agent. From
the four roots, thus operated upon, arise "the colours and forms" of living
things; trees first, both male and female, then fragmentary parts of animals,
heads without necks, and "eyes that strayed up and down in want of a
forehead," which, combined together, produced monstrous forms. These, lacking
power to propagate, perished, and were replaced by "whole-natured" but
sexless "forms" which "arose from the earth," and which, as Strife gained
the upper hand, became male and female. Herein, amidst much
fantastic speculation, would appear to be the germ of the modern theory that
the unadapted become extinct, and that only the adapted survive.
Nature kills off her failures to make room for her
successes.
Anaxagoras, who was a contemporary of Empedocles, interests us
because he was the first philosopher to repair to Athens, and the first
sufferer for truth's sake of whom we have record in Greek annals. Because
he taught that the sun was a red-hot stone, and that the moon had
plains and ravines in it, he was put upon his trial, and but for the
influence of his friend, the famous Pericles, might have suffered
death. Speculations, however bold they be, pass unheeded till they
collide with the popular creed, and in thus attacking the gods, attack
a seemingly divinely settled order. Athens then, and long after,
while indifferent about natural science, was, under the influence of
the revival referred to above, actively hostile to free thinking.
The opinions of Anaxagoras struck at the existence of the gods and
emptied Olympus. If the sky was but an air-filled space, what became of Zeus?
if the sun was only a fiery ball, what became of Apollo? Mr. Grote
says (History of Greece, vol. i, p. 466) that "in the view of the
early Greek, the description of the sun, as given in a modern
astronomical treatise, would have appeared not merely absurd, but repulsive
and impious; even in later times, Anaxagoras and other astronomers
incurred the charge of blasphemy for dispersonifying Hēlios." Of Socrates,
who was himself condemned to death for impiety in denying old gods
and introducing new ones, the same authority writes: "Physics and
astronomy, in his opinion, belonged to the divine class of phenomena, in
which human research was insane, fruitless, and impious." So Demos and
his "betters" clung, as the majority still cling, to the myths of
their forefathers. They repaired to the oracles, and watched for the will
of the gods in signs and omens.
In his philosophy Anaxagoras held that
there was a portion of everything in everything, and that things are
variously mixed in infinite numbers of seeds, each after its kind. From
these, through the action of an external cause, called NOUS, which also is
material, although the "thinnest of all things and the purest," and "has
power over all things," there arose plants and animals. It is probable, as
Professor Burnet remarks, "that Anaxagoras substituted NOUS, still conceived
as a body, for the LOVE and STRIFE of Empedocles simply because he wished
to retain the old Ionic doctrine of a substance that 'knows' all
things, and to identify this with the new theory of a substance that 'moves'
all things."
Thus far speculation has run largely on the origin of
life forms, but now we find revival of speculation about the nature of things
generally, and the formulation of a theory which links Greek cosmology with
early nineteenth-century science with Dalton's ATOMIC THEORY.
Democritus of Abdera, who was born about 460 B. C., has the credit of
having elaborated an atomic theory, but probably he only further developed
what Leucippus had taught before him. Of this last-named philosopher
nothing whatever is known; indeed, his existence has been doubted, but it
counts for something that Aristotle gives him the credit of the discovery,
and that Theophrastus, in the first book of his Opinions, wrote of
Leucippus as follows: "He assumed innumerable and ever-moving elements,
namely, the atoms. And he made their forms infinite in number, since
there was no reason why they should be of one kind rather than another,
and because he saw that there was unceasing becoming and change in
things. He held, further, that _what is_ is no more real than _what is
not_, and that both are alike causes of the things that come into being;
for he laid down that the substance of the atoms was compact and full,
and he called them _what is_, while they moved in the void which he
called _what is not_, but affirmed to be just as real as _what is_." Thus
did "he answer the question that Thales had been the first to
ask."
Postponing further reference to this theory until the great name
of Lucretius, its Roman exponent, is reached, we find a genuine
scientific method making its first start in the person of Aristotle.
This remarkable man, the founder of the experimental school, and the
Father of Natural History, was born 384 B. C. at Stagira in Macedonia. In
his eighteenth year he left his native place for Athens, where he became
a pupil of Plato. Disappointed, as it is thought, at not succeeding
his master in the Academy, he removed to Mytilene in the island of
Lesbos, where he received an invitation from Philip of Macedon to become
tutor to his son, the famous Alexander the Great. When Alexander went on
his expedition to Asia, Aristotle returned to Athens, teaching in
the "school" which his genius raised to the first rank. There he wrote
the greater part of his works, the completion of some of which was
stopped by his death at Chalcis in 322. The range of his studies was
boundless, but in this brief notice we must limit our survey--and the more
so because Aristotle's speculations outside natural history abound
in errors--to his pioneer work in organic evolution. Here, in the
one possible method of reaching the truth, theory follows
observation. Stagira lay on the Strymonic gulf, and a boyhood spent by the
seashore gave Aristotle ample opportunity for noting the variations, and
withal gradations, between marine plants and animals, among which last-named
it should be noted as proof of his insight that he was keen enough
to include sponges. Here was laid the foundation of a classification
of life-forms on which all corresponding attempts were based. Then,
he saw, as none other before him had seen, and as none after him saw
for centuries, the force of heredity, that still unsolved problem
of biology. Speaking broadly of his teaching, the details of which
would fill pages, its main features are (1) His insistence on observation.
In his History of Animals he says "we must not accept a general
principle from logic only, but must prove its application to each fact. For
it is in facts that we must seek general principles, and these must
always accord with facts. Experience furnishes the particular facts from
which induction is the pathway to general laws." (2) His rejection of
chance and assertion of law, not, following a common error, of law
personified as cause, but as the term by which we express the fact that
certain phenomena always occur in a certain order. In his Physics Aristotle
says that "Jupiter rains not that corn may be increased, but from
necessity. Similarly, if some one's corn is destroyed by rain, it does not
rain for this purpose, but as an accidental circumstance. It does not
appear to be from fortune or chance that it frequently rains in winter,
but from necessity." (3) On the question of the origin of life-forms he
was nearest of all to its modern solution, setting forth the necessity
"that germs should have been first produced, and not immediately animals;
and that soft mass which first subsisted was the germ. In plants,
also, there is purpose, but it is less distinct; and this shows that
plants were produced in the same manner as animals, not by chance, as by
the union of olives with grape vines. Similarly, it may be argued,
that there should be an accidental generation of the germs of things, but
he who asserts this subverts Nature herself, for Nature produces
those things which, being continually moved by a certain principle
contained in themselves, arrive at a certain end." In the eagerness of
theologians to discover proof of a belief in one God among the old
philosophers, the references made by Aristotle to a "perfecting principle,"
an "efficient cause," a "prime mover," and so forth, have been too readily
construed as denoting a monotheistic creed which, reminding us of the "one
god" of Xenophanes, is also akin to the Personal God of Christianity.
"The Stagirite," as Mr. Benn remarks (Greek Philosophers, vol. i, p.
312), "agrees with Catholic theism, and he agrees with the First Article
of the English Church, though not with the Pentateuch, in saying that
God is without parts or passions, but there his agreement ceases.
Excluding such a thing as divine interference with all Nature, his theology,
of course, excludes the possibility of revelation, inspiration,
miracles, and grace." He is a being who does not interest himself in
human affairs.
But, differ as the commentators may as to Aristotle's
meaning, his assumed place in the orthodox line led, as will be seen
hereafter, to the acceptance of his philosophy by Augustine, Bishop of Hippo,
in the fourth century, and by other Fathers of the Church, so that the
mediæval theories of the Bible, blended with Aristotle, represent the sum
of knowledge held as sufficient until the discoveries of Copernicus in
the sixteenth century upset the Ptolemaic theory with its fixed earth
and system of cycles and epicycles in which the heavenly bodies moved.
He thereby upset very much besides. Like Anaximander and others,
Aristotle believed in spontaneous generation, although only in the case of
certain animals, as of eels from the mud of ponds, and of insects from
putrid matter. However, in this, both Augustine and Thomas Aquinas, and
many men of science down to the latter part of the seventeenth
century, followed him. For example, Van Helmont, an experimental chemist of
that period, gave a recipe for making fleas; and another scholar
showed himself on a level with the unlettered rustics of to-day, who
believe that eels are produced from horse hairs thrown into a pond.
Of
deeper interest, as marking Aristotle's prevision, is his anticipation of
what is known as Epigenesis, or the theory of the development of the germ
into the adult form among the higher individuals through the union of the
fertilizing powers of the male and female organs. This theory, which was
proved by the researches of Harvey, the discoverer of the circulation of the
blood, and is accepted by all biologists to-day, was opposed by Malpighi, an
Italian physician, born in 1628, the year in which Harvey published his great
discovery, and by other prominent men of science down to the last century.
Malpighi and his school contended that the perfect animal is already
"preformed" in the germ; for example, the hen's egg, before fecundation,
containing an excessively minute, but complete, chick. It therefore followed
that in any germ the germs of all subsequent offspring must be contained,
and in the application of this "box-within-box" theory its defenders
even computed the number of human germs concentrated in the ovary of
mother Eve, estimating these at two hundred thousand millions!
When
the "preformation" theory was revived by Bonnet and others in the eighteenth
century, Erasmus Darwin, grandfather of Charles Darwin, passed the following
shrewd criticism on it: "Many ingenious philosophers have found so great
difficulty in conceiving the manner of reproduction in animals that they have
supposed all the numerous progeny to have existed in miniature in the animal
originally created. This idea, besides its being unsupported by any analogy
we are acquainted with, ascribes a greater continuity to organized matter
than we can readily admit. These embryons ... must possess a greater degree
of minuteness than that which was ascribed to the devils who tempted
St. Anthony, of whom twenty thousand were said to have been able to
dance a saraband on the point of a needle without the least incommoding
each other."
Although no theistic element could be extracted by the
theologians of the early Christian Church from the systems of Empedocles
and Democritus, thereby securing them a share in the influence exercised
by the great Stagirite, they were formative powers in Greek
philosophy, and, moreover, have "come by their own" in these latter days.
Their chief representative in what is known as the Post-Aristotelian period
is Epicurus, who was born at Samos, 342 B. C. As with Zeno, the founder
of the Stoic school, his teaching has been perverted, so that his name
has become loosely identified with indulgence in gross and sensual
living. He saw in pleasure the highest happiness, and therefore advocated
the pursuit of pleasure to attain happiness, but he did not thereby mean
the pursuit of the unworthy. Rather did he counsel the following after
pure, high, and noble aims, whereby alone a man could have peace of mind.
It is not hard to see that in the minds of men of low ideals the
tendency towards passivity which lurked in such teaching would aid their
sliding into the pursuit of mere animal enjoyment; hence the gross and
limited association of the term Epicurean. Epicurus accepted the theory
of Leucippus, and applied it all round. The _faineant_ gods, who
dwell serenely indifferent to human affairs, and about whom men
should therefore have no dread; all things, whether dead or living,
even the ideas that enter the mind; are alike composed of atoms. He
also accepted the theory broached by Empedocles as to the survival of fit
and capable forms after life had arrived at these through the processes
of spontaneous generation and the production of monstrosities. Adopting
the physical speculations of these forerunners, he made them the vehicle
of didactic and ethical philosophies which inspired the production of
the wonderful poem of Lucretius.
Between this great Roman and
Epicurus--a period of some two centuries--there is no name of sufficient
prominence to warrant attention. The decline of Greece had culminated in her
conquest by the semi-barbarian Mummius, and in her consequent addition to the
provinces of the Roman Empire. What life lingered in her philosophy within
her own borders expired with the loss of freedom, and the work done by
the Pioneers of Evolution in Greece was to be resumed elsewhere. In
the few years of the pre-Christian period that remained the teaching
of Empedocles, and of Epicurus as the mouthpiece of the atomic theory,
was revived by Lucretius in his De Rerum Natura. Of that remarkable man
but little is recorded, and the record is untrustworthy. He was
probably born 99 B. C., and died--by his own hand, Jerome says, but of this
there is no proof--in his forty-fourth year. It is difficult, taking up
his wonderful poem, to resist the temptation to make copious extracts from
it, since, even through the vehicle of Mr. Munro's exquisite translation, it
is probably little known to the general reader in these evil days of snippety
literature. But the temptation must be resisted, save in moderate
degree.
With the dignity which his high mission inspires, Lucretius
appeals to us in the threefold character of teacher, reformer, and poet.
"First, by reason of the greatness of my argument, and because I set the mind
free from the close-drawn bonds of superstition; and next because, on so
dark a theme, I compose such lucid verse, touching every point with the
grace of poesy." As a teacher he expounds the doctrines of Epicurus
concerning life and nature; as a reformer he attacks superstition; as a poet
he informs both the atomic philosophy and its moral application
with harmonious and beautiful verse swayed by a fervour that is akin
to religious emotion.
Discussing at the outset various theories of
origins, and dismissing these, notably that which asserts that things came
from nothing--"for if so, any kind might be born of anything, nothing would
require seed," Lucretius proceeds to expound the teaching of Leucippus and
other atomists as to the constitution of things by particles of matter
ruled in their movements by unvarying laws. This theory he works all
round, explaining the processes by which the atoms unite to carry on the
birth, growth, and decay of things, the variety of which is due to variety
of form of the atoms and to differences in modes of their combination;
the combinations being determined by the affinities or properties of
the atoms themselves, "since it is absolutely decreed what each thing
can and what it cannot do by the conditions of Nature." Change is the law
of the universe; what is, will perish, but only to reappear in
another form. Death is "the only immortal"; and it is that and what may
follow it which are the chief tormentors of men. "This terror of the
soul, therefore, and this darkness, must be dispelled, not by the rays
of the sun or the bright shafts of day, but by the outward aspect
and harmonious plan of Nature." Lucretius explains that the soul, which
he places in the centre of the breast, is also formed of very minute
atoms of heat, wind, calm air, and a finer essence, the proportions of
which determine the character of both men and animals. It dies with the
body, in support of which statement Lucretius advances seventeen arguments,
so determined is he to "deliver those who through fear of death are
all their lifetime subject to bondage."
These themes fill the first
three books. In the fourth he grapples with the mental problems of sensation
and conception, and explains the origin of belief in immortality as due to
ghosts and apparitions which appear in dreams. "When sleep has prostrated the
body, for no other reason does the mind's intelligence wake, except because
the very same images provoke our minds which provoke them when we are awake,
and to such a degree that we seem without a doubt to perceive him whom life
has left, and death and earth gotten hold of. This Nature constrains to come
to pass because all the senses of the body are then hampered and at
rest throughout the limbs, and cannot refute the unreal by real
things."
In the fifth book Lucretius deals with origins--of the sun, the
moon, the earth (which he held to be flat, denying the existence of
the antipodes); of life and its development; and of civilization. In all
this he excludes design, explaining everything as produced and maintained by
natural agents, "the masses, suddenly brought together, became the rudiments
of earth, sea, and heaven, and the race of living things." He believed in the
successive appearance of plants and animals, but in their arising separately
and directly out of the earth, "under the influence of rain and the heat of
the sun," thus repeating the old speculations of the emergence of life from
slime, "wherefore the earth with good title has gotten and keeps the name of
mother." He did not adopt Empedocles's theory of the "four roots of all
things," and he will have none of the monsters--the hippogriffs, chimeras,
and centaurs--which form a part of the scheme of that philosopher.
These, he says, "have never existed," thus showing himself far in advance
of ages when unicorns, dragons, and such-like fabled beasts were
seriously believed to exist. In one respect, more discerning than Aristotle,
he accepts the doctrine of the survival of the fittest as taught by
the sage of Agrigentum. For he argues that since upon "the increase of
some Nature set a ban, so that they could not reach the coveted flower
of age, nor find food, nor be united in marriage," ... "many races
of living things have died out, and been unable to beget and
continue their breed." Lucretius speaks of Empedocles in terms scarcely
less exaggerated than those which he applied to Epicurus. The latter is "a
god" "who first found out that plan of life which is now termed wisdom, and
who by tried skill rescued life from such great billows and such thick
darkness and moored it in so perfect a calm and in so brilliant a light, ...
he cleared men's breasts with truth-telling precepts, and fixed a limit to
lust and fear, and explained what was the chief good which we all strive to
reach." As to Empedocles, "that great country (Sicily) seems to have held
within it nothing more glorious than this man, nothing more holy, marvellous,
and dear. The verses, too, of this godlike genius cry with a loud voice, and
make known his great discoveries, so that he seems scarcely born of a mortal
stock."
Continuing his speculations on the development of living
things, Lucretius strikes out in bolder and original vein. The past history
of man, he says, lies in no heroic or golden age, but in one of
struggle out of savagery. Only when "children, by their coaxing ways,
easily broke down the proud temper of their fathers," did there arise
the family ties out of which the wider social bond has grown, and
softening and civilizing agencies begin their fair offices. In his battle for
food and shelter, "man's first arms were hands, nails and teeth and
stones and boughs broken off from the forests, and flame and fire, as
soon as they had become known. Afterward the force of iron and copper
was discovered, and the use of copper was known before that of iron, as
its nature is easier to work, and it is found in greater quantity.
With copper they would labour the soil of the earth and stir up the
billows of war.... Then by slow steps the sword of iron gained ground and
the make of the copper sickle became a byword, and with iron they began
to plough through the earth's soil, and the struggles of wavering man
were rendered equal." As to language, "Nature impelled them to utter
the various sounds of the tongue, and use struck out the names of
things." Thus does Lucretius point the road along which physical and
mental evolution have since travelled, and make the whole story subordinate
to the high purpose of his poem in deliverance of the beings whose
career he thus traces from superstition. Man "seeing the system of heaven
and the different seasons of the years could not find out by what
causes this was done, and sought refuge in handing over all things to the
gods and supposing all things to be guided by their nod." Then, in the
sixth and last book, the completion of which would seem to have been
arrested by his death, Lucretius explains the "law of winds and storms,"
of earthquakes and volcanic outbursts, which men "foolishly lay to
the charge of the gods," who thereby make known their
anger.
So, loath to suffer mute, We, peopling the
void air, Make Gods to whom to impute The ills we
ought to bear; With God and Fate to rail at, suffering easily. |
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