LITTLE BLUE BOOK NO. =608=
Edited by E. Haldeman-Julius
The Origin and
Development of
the Atomic Theory
Maynard Shipley
HALDEMAN-JULIUS COMPANY
GIRARD, KANSAS
Copyright, 1924
Haldeman-Julius Company
PRINTED IN THE UNITED STATES OF AMERICA
THE ORIGIN AND DEVELOPMENT OF
THE ATOMIC THEORY
CONTENTS
PAGE
CHAPTER I—THE PYTHAGOREAN ATOMISTS 5
CHAPTER II—THE MATERIALISTIC ATOMISTS:
LEUCIPPUS AND DEMOCRITUS 22
CHAPTER III—THE ELEATIC VIEW 37
CHAPTER IV—EPICURUS AND LUCRETIUS 51
CHAPTER V—POST-CLASSICAL ATOMISM 59
THE ORIGIN AND DEVELOPMENT OF THE ATOMIC THEORY
CHAPTER I
THE PYTHAGOREAN ATOMISTS
THE SIGNIFICANCE OF THE ATOMIC THEORY
It is safe to say that there is no more romantic story in the history
of science than that of the origin and development of the atomic
theory of matter. Dr. Robert A. Millikan has said that the physical
principles laid down by Leucippus in the fifth century before our era
might, with a few modifications and omissions, “almost pass muster
today” (“The Electron,” Page 7). The importance to modern students of
sound knowledge of the teachings of the ancient Atomists was emphasized
by Sir William Osler (1829-1919), who even went so far as to say that
“the student of physics may know Crookes’ tubes and their relation to
Roentgen, but he cannot have a true conception of the atomic theory
without a knowledge of Democritus; and the exponent of Madame Curie and
of Sir J. J. Thomson will find his happiest illustrations from the
writings of Lucretius”[1]--the Roman exponent of Epicurus (342-270 B.
C.), who revived the atomic theory of Leucippus and Democritus, despite
the adverse criticisms hurled at this doctrine by the great Aristotle.
Le Sage observed that “if Epicurus had had but a part of the
geometrical knowledge of his contemporary Euclid, and conceptions of
cosmogony the same as many then living, he might have discovered the
laws of universal gravity, and not only the laws, but, what was the
despair of Newton, its mechanical cause” (“_Lucrèce Newtonien_,”
Berlin Academy, 1782).
Writing of the value to science and modern thought of the atomic theory
of the early Greek philosophers, Professor Walter T. Marvin, of Rutgers
College, points out that a theory can be significant in at least three
ways, namely:--“(1) by destroying or inhibiting other beliefs; (2) by
arousing interest in new problems and by suggesting new methods of
investigation; (3) by what it itself enables us to explain correctly.
This theory was most significant in destroying old beliefs or, to
adopt a much used expression, in ‘_enlightening_’ the cultured
Greeks. A thoughtful Greek could hardly believe that the universe is
a cloud of atoms moving about in accordance with necessary mechanical
laws, and at the same time continue to believe the primitive traditions
and superstitions of his people. The worship of the gods and the old
magical rites and ceremonies must needs seem to him utterly ineffective
and useless, valuable customs no doubt for their purely psychological
influence upon the ignorant and unruly masses but of course absurdities
for the cultured and disciplined man. Hence no wonder that the spread
of this and the preceding cosmological theories would result, in
a society such as that of the Greek world in the sixth and fifth
centuries B. C., in a _radical enlightenment_. No wonder that
their spread was opposed by men of conservative tendencies. In this
first respect early Greek science and in particular the atomic theory
were of great historical significance.”[2]
THE ATOMIC THEORY OF THE PYTHAGOREANS
In the ancient Sanskrit literature of India (written prior to 500 B.
C.), an atomic theory of matter is formulated by Kanada (literally
“atom eater”--a term of derision), founder of the Nyaga system of
philosophy, and said to have been a pupil of Buddha. He states that the
atoms are eternal and that the ultimate atom is simple.
Kapila, the leading exponent of the Sankhya philosophy, speaks of
“five subtle” kinds of particles (atoms), and a substance akin to our
luminiferous ether--the five particles being, no doubt, the “five
elements” of the Laws of Menu; viz., earth, water, wind (air), fire and
ether--this last the parent, so to speak, of all the other elements,
through a process of successive transformations.
In the “Angutarra Nikaja,” consciousness (mind) is mentioned as a sixth
element, also atomic in structure.
In his “History of Hindu Chemistry,” Sir P. C. Ray expresses the
opinion that the atomic theory of the ancient Greeks was derived
directly from the more ancient Hindu doctrine--a view upheld by the
great German Sanskrit scholar, Dr. Max Müller, as also by some Greek
scholars.
_The_ atomic theory, the earliest known to have been worked out in
detail, is that of the Greek philosopher Leucippus, of Miletus, Ionia;
though the mantle of honor has fallen mostly on the shoulders of his
far better known pupil, Democritus of Abdera, Thrace.
But the Pythagoreans also were exponents of a form of atomic theory,
and it seems probable that Pythagoras, a native of the island of Samos,
was the first Greek to advance the doctrine of the discontinuity of
matter. At least, none of his disciples ever claimed to have been the
originator of this doctrine, and Pythagoras was born some time between
580 and 570 B. C., while the Atomic School of Leucippus was not founded
until some time after 500 B. C. Unfortunately, Pythagoras did not
commit his doctrines to writing, though a few of the so-called “Golden
Sentences” may have been written by him. Most of them, however, are
probably no older than the fourth century of our era. Moreover, these
throw no light on the subject under discussion.
The first written exposition of the Pythagorean atomic theory was put
forward by Philolaus, a native of Tarentum, South Italy. Only fragments
of his work have survived, and of those ascribed to him some are
undoubtedly spurious. But all of them are very old and contain valuable
information concerning Pythagorean doctrines.
Porphyry (233-304? A. D.), a Syrian Neo-Platonist, residing for some
years in Alexandria, wrote a “Life of Pythagoras,” and a few years
later another “Life” of this philosopher appeared, this time from
the pen--or stylus--of another Syrian and Neo-Platonist, Iamblichus.
But these works contain much that is wholly mythical concerning
Pythagoras.[3]
Our best sources of information are Plato (_Timaeus_), Aristotle
(_Metaphysica and Physica_, _De Anima and De Caelo_), Diogenes Laertius
(_De Vitis_) and Stobaeus (_Eclogarum physicarum et ethicarum_). From
these authorities we learn that, according to the Pythagoreans, the
cosmos was at a certain stage of its (cyclic) changes a compact, inert,
spherical mass of lifeless matter, having no distinguishable parts.
After a long period of quiescence the “void”--i. e., the limitless
outer air--broke in upon the world, entering into “the heaven itself”
as if it--the heaven--were breathing. The result of this cosmic
inhalation was “a certain separation and definition of things that
lie together” (Aristotle, _Physica_, iv, 6)--that is, a separation of
the homogeneous mass into different “elements.” These fragments were
eventually ground into an all but infinite number of infinitesimal
particles, or “monads,” analogous to the “atoms” of Leucippus and
Democritus.
Now, Philolaus was a famous geometrician as well as an eminent
physician and astronomer. Hence he--and presumably Pythagoras before
him--thought of these particles (or atoms) not in terms of various
qualities, chemically considered,--as Anaxagoras (500-428 B. C.), who
was not a Pythagorean, had done before Philolaus wrote--but in terms
of form (shape) and number. Each of the various substances known to
the ancient world as “elements”--generally recognized as compounds of
the real elements since the eighteenth century only--was regarded as
made up of particles of a certain geometrical configuration. Philolaus
explained that the “element” earth was composed of cubical particles,
fire of tetrahedra (pyramidal forms), and the “ether” was identified
with the dodecahedron (particles having twelve plane faces, or twelve
regular pentagons). In the _Timaeus_ of Plato we find this
conception further developed, bringing all the five regular solids into
the theory. Thus, the octahedron was now assigned to air, and the
icosahedron (a figure having twenty equilateral triangular faces) to
water.
Very interesting in this connection is the fact that the positions of
the electrons in atoms (the real elements) are being referred to today
in terms similar to those employed by the Pythagoreans. Take, for
example, the following passage from _Science Progress_ (London),
July, 1922 (No. 65), Pages 21-22:
“The modifications proposed in the expressions for electric and
magnetic forces allow of the electrons in [Sir J. J.] Thomson’s
model [atoms] to take up positions at rest at the corners of certain
well-known polyhedra, such as the tetrahedron, the cube, the rhombic
dodecahedron, the cubo-octahedron; and so in the sharing of electrons
between atoms and the consequent fitting together of such models we
have the explanation of certain facts of crystallography.”
But we know now that “fire” is not an “element” composed of tetrahedral
atoms; but the combustible portion of coal and wood is the real element
_carbon_--and the carbon molecule _is_ of tetrahedral form.
(See Bragg, Sir W. H. and W. L., “X-Rays and Crystal Spectra.”)
On the Pythagorean theory--as on that of Leucippus, and on the latest
theories of today--matter is broken up into parts (atoms) that are in
themselves unchangeable--apart from radioactivity--but produce by their
changes of position in relation to one another all the substances of
earth and of living organisms.
To illustrate this principle in terms of modern science: Add four
electrons (two positive and two negative) to the hydrogen atom, and
you have the element lithium; knock out of the lithium atom (composed
of three positive and three negative electrons) one positive and
one negative electron, and you have one atom of helium (composed of
two positive and two negative electrons.) And _electrons are all
alike_, except that some carry a charge of positive electrification
and some a negative charge--each kind (species) of atom having an
equal number of positive and negative charges, thus attaining stable
equilibrium. (See Soddy, _The Interpretation of Radium_, 1922.)
Until quite recently it was believed that atoms could be disrupted
only by temperatures higher than those obtainable in our physical
laboratories, or by bombardment by electrons and helium atoms
spontaneously expelled (always with enormous velocities) from
radioactive substances. But this is now known to be an erroneous
assumption. It was lately discovered by P. M. Basset, engineer of
the Sperry Gyroscope Company, and Dr. Louis Bell, that when carbon
is brought to a temperature of 5,000° C., in an arc-light used in
connection with their amazingly powerful searchlight, alpha particles
(helium atoms) are liberated. Such discoveries may some day lead to
the transmutation of “the baser metals into gold,” thus fulfilling the
dream of the alchemists of old.
Quite recently, Drs. Milliken and Bowen not only developed a method
for “stripping” planetary (valence) electrons one by one from atoms,
but these investigations also proved that Bohr’s (simple) theory
of electron orbits--which includes the statement that the energy
developed when an electron jumps from one orbit to another is exactly
proportional to the frequency (or wave-length) emitted--is correct.
Professor Sommerfeld’s theory explaining the cause of double lines
in the spectrum of hydrogen and other elements was also verified
experimentally. (See _The Scientific Monthly_, Pages 665-669,
June, 1924).
An atom of mercury, for example, contains 80 positive charges
(electrons) on its nucleus, and 80 negative outlying electrons. Were
we able to expel two of its _protons_ (positive electrons), it
would instantly become the metal platinum. If a negative (“planetary”)
electron were also taken from it, the mercury atom would then have
lost two positive charges (electrons) and one negative; that is, one
positive charge on the whole: and hence it would retain 79 positive
charges on the nucleus and 79 outlying negative electrons--and thus
_become gold_!
Thus, one element differs from another only in the number of electrons
composing its atom. And this is only a more precise statement of the
essential doctrine of the ancient Greek atomists.
Parmenides, the Eleatic philosopher, who was at the height of his
fame about 475 B. C., declared that both motion and change of
substance were illusory--that no substances ever transform from one
to another. The Pythagoreans and the School of Leucippus admitted
that there was, indeed, an element of elements that knew no change,
no transformations; and they declared that this primal element was
the stuff that _all_ atoms are made of. Today we believe his
primal element (atom) to be hydrogen--as was suggested by the English
physician, William Prout, in 1815. In other words, we are being forced
by the mathematical and experimental data to conclude that all of
the 87 known species of atoms (or elements) are but compounds of the
original (simplest) hydrogen atom, consisting of one positively charged
nuclear electron and one outlying negative electron. However, there
is ground for difference of opinion on this question, as shown by Sir
Oliver Lodge in his recent article, “Within the Atom,” _Scientific
American_, November, 1923.
“Thought,” comments Professor Alfred Weber (“History of Philosophy,”
Pages 43-44), “discovers in the atomistic hypothesis the middle
term that unites Parmenides, who denies the great empirical fact of
generation and change, and Heraclitus, who sacrifices being and its
permanence to becoming,--thereby combining the two rival systems
into a higher synthesis,--and lays the foundation for every rational
explanation of the process of becoming. Henceforth philosophy no
longer regards matter as a continuous mass, the essential properties
of which are incessantly transformed. It breaks them up into parts
that are in themselves immutable, but which continually change their
relative positions. As a consequence, there can be both perpetual
change in the aspects of matter (bodies) and permanence in the essence
and properties of matter. All change is reduced to change of place:
_mechanism_.”
THE FIERY “MONADS” (ATOMS)
“Fire,” with the Pythagoreans, as with the followers of Heraclitus of
Ephesus (535-475 B. C.), is _the_ element _par excellence_;
and, as previously stated, was regarded by them as made up of
excessively minute particles of tetrahedral (pyramidal) form
(Philolaus). This “subtile element” was looked upon as the symbol
of the divine principle in nature. They taught that this “fire” is
concentrated in a central sun, “the hearth of the universe,” “mother
of the gods,” “citadel of Zeus,” etc., around which revolve the earth
and the other heavenly bodies.[4] The soul of man is a portion of the
world-soul, a spark of the celestial fire, and in this sense material.
Aristotle states (_De Anima_, i, 2) that some of the Pythagoreans
held the solar corpuscles (atoms) to be souls, while others referred
to that which set them in motion as the soul. Schlottman’s reading of
this passage is: “The solar corpuscles are moved by a soul, and the
soul is, generally speaking, the moving principle.”
Professor Burnet calls attention to the singular power exhibited by
the Pythagoreans in adapting their theories to conditions; and among
certain radical changes in their point of view, he thinks the most
remarkable is the way the religious side of the doctrine was gradually
dropped. “The effort was made to clear the name of Pythagoras himself
from the imputation of mysticism. We have the echo of this in the
remains of Aristoxenos and Dikairchos, but it must be older; for in
their day scientific Pythagoreans had ceased to exist. The statement
that Hippasos of Metapontium was guilty of publishing a mystic
discourse ‘with the view of misrepresenting Pythagoras’ (Diogenes,
viii, 7) must go back to this generation of the school; for at a later
date no one would have any interest in making it.”[5]
According to Stobaeus (_Eclogarum physicarum et ethicarum_, i,
308), Ecphantus--an immediate successor of Pythagoras, according to
Röth--was the first philosopher to explain the Pythagorean monads
(atoms) as something corporeal. But this view is regarded by most
authorities as being contrary to the doctrine of the Pythagoreans.
While Ecphantus is included among the disciples of the School, his
doctrine of material atoms as the original constituents of the
Pythagorean “numbers,” as well as of matter, cannot, according to
Zeller, have been derived from his reputed master. Unlike the followers
of Leucippus, Ecphantus believed, with Anaxagoras (500-428 B. C.),
that the movement of the atoms (or monads), as well as the formation
of the universe, was produced by mind or soul. Atoms, according to
Ecphantus, differ among themselves in size, form and _force_. It
is interesting to note that this philosopher had not only accepted as
true the affirmation of Pythagoras that the earth is a sphere, but he
knew also that it rotated upon its axis (Schiaparelli, “_I Precursori
di Copernico nell’Antichita_,” in _Memorie del Reale Instituto
Lombardi_, xii).
Here, then, paradoxically enough, we find in the teachings of the
idealistic Pythagoreans the roots of our modern theories of cosmogony
and the atomic theory of matter. Their “particles” are qualitatively
all alike, differing only in form. By changes in their number and
position these qualitatively homogeneous atoms form all the various
substances of earth, sea and sky.
THE “SEEDS” OF ANAXAGORAS (500-428 B. C.)
The “seeds” (or germs) of Anaxagoras must also, in a sense, be
considered “atoms.” But, so far from being all alike fundamentally,
for him each substance was supposed to be composed of its own peculiar
particles, there being as many kinds of “seeds” as there are kinds of
substances.
Whence came this more or less novel doctrine? Was it wholly original
with the sage of Clazomeniæ? Leucippus, the founder of “the
materialistic” atomic theory, was a contemporary of Anaxagoras, and
both lived after the time of Pythagoras, and may have been indebted
either to him or to suggestions from India for their fundamental
physical conceptions, finding them, indeed, fully accordant with
the primary postulates of the older Ionian physicists--Anaximines
(524-508 B. C.), Anaximander (611-547 B. C.) and Thales (624?-548?
B. C.). All of these believed that all elements are but compounds or
transformations of one primitive element.
It is natural to inquire here how such “suggestions from India” could
have reached Greece. Professor Gompertz, while he does not discuss
the possible Indian origin of the atomic theory, would have an answer
to this question. He admits that the Greeks “owe to the Orient the
elements of material civilization” and much of their science, art and
religion to older civilizations. How were these transferred to Greece?
This question, he recalls, brings up a striking parallel from the
literary history of mediæval Europe. “Practically the entire fairy-lore
of the Occident is derived from India. No one,” he goes on to say,
“disputes this assertion today”; yet, on the other hand, “no one as yet
can give a completely clear account of the ways and means by which its
journey was accomplished” (“Greek Thinkers,” Page 95).
FOOTNOTES:
[Footnote 1: “Studies in the History and Method of Science,” edited by
Dr. Charles Singer, Oxford, 1917.]
[Footnote 2: “The History of European Philosophy,” Page 105, New York,
1917.]
[Footnote 3: Cf. Nauck, A., _Porphyrii Opusculati Selecta_, ed.
2, Leipsic, 1886; and _Iamblichi De Vita Pythagorica Liber_, ed.
Nauck, Petrograd, 1884; Chaignet, “_Pythagore et la Philosophie
Pythagoricienne_,” Paris, 1873. See also Cantor, “_Vorlesungen
uber die Geshichte der Mathematik_,” I, 124 ff.]
[Footnote 4: Thus laying the foundation for the true heliocentric
theory, introduced by Aristarchus of Samos about 280 B. C.--a theory
accepted and developed by Seleucus of Seleucia in Babylonia, but
rejected in the following century by the greatest of the Greek
astronomers, Hipparchus of Nicæa, discoverer of the “precession of the
equinoxes,” and author of a catalogue of 1000 fixed stars.]
[Footnote 5: Burnet, Professor John, “Greek Philosophy,” Vol. I, ¶70,
Page 87, London, 1914. See also, by the same author, “Early Greek
Philosophy,” 2 ed., ¶¶138 sq.]