KEPLER.

The acceptance of a doctrine is often out of all proportion to the

authority that fortifies it. There are sweeps of generalization quite

permeable to objection, which yet find metaphysical support; there are

irrefragable dogmas which the mind drops as futile and fruitless. It is

recorded of Harvey's discovery of the circulation of the blood, that it

found reception from no physician then over forty years old. We believe

the splendid nebular construction of Laplace has its own difficulties;

yet what noble or aspiring mind does not find interior warranties for

the truth of that audacious synthesis? Is it that the soul darts

responsive impartments to the heavens? that the whirl is elemental in

the mind? that baffling intervals stretch deeper within us, and shoals

of stars with no parallax appear?

Among the functions of Science, then, may well be included its power as

a metre of the intellectual advance of mankind. In these splendid

symbols man writes the record of his advancing humanity. How all is

interwoven with the All! A petrified national mind will certainly

appear in a petrified national Science. And that sublime upsurging from

the depths of human nature which came with the last half of the

eighteenth century appeared not alone in the new political and social

aspirations, but in a fresh insight into Nature. This spirit manifested

itself in the new sciences that sprang from the new modes of

vision,--Magnetism, Electricity, Chemistry,--the old crystalline spell

departing before a dynamical system of Physics, before the thought of

the universe as a living organic whole. And what provokers does the

discovery of the celestial circles bring to new circles of politics and

social life!

The illustrations of Astronomy to this thought are very large. First of

the sciences to assume a perfectly rational form, it presents the

eternal type of the unfolding of the speculative spirit of man. This

springs, no doubt, from the essentially subjective character of

astronomy,--more than all the other sciences a construction of the

creative reason. From the initiative of scientific astronomy, when the

early Greek geometers referred the apparent diurnal movements to

geometrical laws, to the creation of the nebular hypothesis, the

logical filiation of the leading astronomical conceptions obeys

corresponding tidal movements in humanity. Thus it is that

"through the ages one increasing purpose

runs

And the thoughts of men are widened with the

process of the suns."

It was for reasons the Ptolemaic system so long held its sway. It was

for reasons it went, too, when it did, hideous and oppressive

nightmare! The celestial revelations of the sixteenth century came as

the necessary complement of the new mental firmaments then dawning on

the thought of man. The intellectual revolution caused by the discovery

of the double motion of our planet was undoubtedly the mightiest that

man had ever experienced, and its effect was to change the entire

aspect of his speculative and practical activity. What a proof that

ideas rule the world! Two hundred and fifty years ago, certain new

sidereal conceptions arose in the minds of half a dozen philosophers,

(isolated and utterly destitute of political or social influence,

powerful only in the possession of a sublime and seminal

thought,)--conceptions which, during these two centuries, have

succeeded in overthrowing a doctrine as old as the human mind, closely

interknit with the entire texture of opinions, authority, politics, and

religion, and establishing a theory flatly contradicted by the

universal dictates of experience and common sense, and true only to the

transcendental and interpretative Reason!

At the advent of Modern Astronomy, the apparition of the German, John

Kepler, presents itself. Familiarly associated in general apprehension

with that inductive triad known as "Kepler's Laws," which form the

foundation of Celestial Geometry, it is much less generally known that

he was an august and oracular soul, one of those called Mystics and

Transcendentalists, perhaps the greatest genius for analogy that ever

lived,--that he led a truly epic life, a hero and helper of men, a

divine martyr of humanity.

The labors of Kepler were mathematical, optical, cosmographical, and

astronomical,--but chiefly astronomical. Two or three of his principal

works are the "Cosmographic Mystery," (_Mysterium Cosmographicum,_) the

"New Astronomy," (_Astronomia Nova, seu Physica Caelestis,_) and the

"Harmonies of the World" (_Harmonices Mundi_). His whole published

works comprise some thirty or forty volumes, while twenty folio volumes

of manuscript lie in the Library at St. Petersburg. These Euler,

Lexell, and Kraft undertook some years ago to examine and publish, but

the result of this examination has never appeared. An elegant complete

edition of the works of Kepler is at present being issued at Frankfort,

under the editorship of Frisch.[1] It is to be in sixteen volumes, 8vo,

two of which are published. For his biography, the chief source is the

folio volume of Correspondence, published in 1718, by Hansch,[2] who

has prefixed to these letters between Kepler and his contemporaries a

Life, in which his German heartiness beats even through the marble

encasement of his Latinity.

[Footnote 1: _Joannis Kepleri Astronomi Opera Omnia._ Edidit CH.

FRISCH.]

[Footnote 2: _Epistolae ad Joannem Keplerum scriptae._ MICHAEL GOTTLIEB

HANSCHIUS. Lipsiae, 1718.]

We have always admired, as a stroke of wit, the way Hansch takes to

indicate Kepler's birthplace. Disdaining to use any but mathematical

symbols for so great a mathematician, he writes that he was born on the

21st of December, 1571, in longitude 29° 7', latitude 48° 54'! It may

be worth mentioning, that on this cryptic spot stood the little town of

Weil in the Duchy of Würtemberg. His birth was cast at a time when his

parents were reduced to great poverty, and he received very little

early schooling. He was, however, sent to Tübingen, and here he pursued

the scholastic studies of the age, designing for the Church. But the

old eternal creed-questionings arose in his mind. He stumbled at the

omnipresence of Christ's body, wrote a Latin poem against it, and, when

he had completed his studies, got for a _testimonium_ that he had

distinguished himself by his oratorical talents, but was considered

unfit to be a fellow-laborer in the Church of Würtemberg. A larger

priesthood awaited him.

The astronomical lectureship at the University of Grätz, in Styria,

falling vacant, Kepler was in his twenty-third year appointed to fill

it. He was, as he tells us, "better furnished with talent than

knowledge." But, no doubt, things had conspired to forward him. While

at Tübingen, under the mathematician Mästlin, he had eagerly seized

all the hints his master threw out of the doctrines of Copernicus,

integrating them with interior authorities of his own. "The motion of the

earth, which Copernicus had proved by mathematical reasons, I wanted

to prove by physical, or, if you prefer it, metaphysical reasons."

So he wrote in his "Prodromus Dissertationum Cosmographicarum,"

which he published two years after going to Grätz, that is, in his

twenty-fifth year. In this book his fiery and mystical spirit first

found expression, flaming forth in meteoric coruscations. The problem

which Kepler attempted to solve in the "Prodromus" was no less than

the determination of the harmonic relations of the distances of

the planets, which it was given him to solve more than twenty years

afterwards. The hypothesis which he adopted proved utterly fallacious;

but his primal intuition, that numerical and geometric relations

connect the velocities, periods, and distances of the planets, was none

the less fruitful and sublime.

Of the facts of Kepler's external life, we may simply say, for the sake

of readier apprehension, that, after remaining six years at Grätz, he,

in 1600, on the invitation of Tycho Brahe, Astronomer Royal to Rodolph

II. of Germany, removed to Prague and associated himself with Tycho,

who shortly afterwards dying, Kepler was appointed in his place. The

chief work was the construction of the new astronomical tables called

the Rodolphine Tables, and on these he was engaged many years. In this

situation he continued till 1613, when he left it to assume a

professorship at Linz. Here he remained some years, and the latter part

of his life was spent as astrologer to Wallenstein. Kepler is described

as small and meagre of person, and he speaks of himself as "troublesome

and choleric in politics and domestic matters." He was twice married,

and left a wife and numerous children ill-provided for.

Indeed, a painful and perturbed life fell to the lot of Kepler. The

most crushing poverty all his life oppressed him. For, though his

nominal salary as Astronomer Royal was large enough, yet the treasury

was so exhausted that it was impossible for him ever to obtain more

than a pittance. What a sad tragedy do these words, in a letter to

Mästlin, reveal:--"I stand whole days in the antechamber, and am nought

for study." And then he adds the sublime compensation: "I keep up my

spirits, however, with the thought that I serve, not the Emperor alone,

but the whole human race,--that I am laboring not merely for the

present generation, but for posterity. If God stand by me and look to

the victuals, I hope to perform something yet." Eternal type of the

consolation which the consciousness of truth brings with it, his

ejaculation on the discovery of his third law remains one of the

sublimest utterances of the human mind:--"The die is cast; the book is

written,--to be read now or by posterity, I care not which: it may well

wait a century for a reader, as God has waited six thousand years for

an observer!" Cast in a stormy and chaotic age, he was persecuted by

both Protestants and Catholics on account of the purity and elevation

of his religious ideas; and from the disclosures of Baron von

Breitschwert [1] it seems, that, in the midst of his sublimest labors,

he spent five years in the defence of his poor old mother against a

charge of witchcraft. He died in 1630, in his sixtieth year, (with the

prospect of starvation before him,) of a fever which he caught when on

a journey to Ratisbon, whither he had gone in the attempt to get part

of his pay!

[Footnote 1: _Johann Keppler's Leben und Wirken: nach neuerlich

aufgefundenen Manuscripten bearbeitet._ Stuttgart, 1813.]

In what bewildering and hampering environment he found himself with the

"Tübingen doctors" and the "Würtemberg divines," his letters reveal. On

the publication of the "Prodromus," Hafenreffer wrote to warn

him:--"God forbid you should endeavor to bring your hypothesis openly

into argument with the Holy Scriptures! I require of you to treat the

subject merely as a mathematician, and to leave the peace of the Church

undisturbed." To the Tübingen doctors he replied:--"The Bible speaks to

me of things belonging to human life as men are used to speak of them.

It is no manual of Optics or of Astronomy; it has a higher object in

view. It is a culpable misuse of it to seek in it for answers on

worldly things. Joshua wished for the day to be lengthened. God

hearkened to his wish. How? This is not to be inquired after." And

surely the long-vexed argument has never since unfolded better

statement than in the words of Kepler:--"The day will soon break when

pious simplicity will be ashamed of its blind superstition,--when men

will recognize truth in the book of Nature as well as in the Holy

Scriptures, and rejoice in the two revelations." [1]

[Footnote 1: _Harmonices Mundi._]

On this avowal he was branded as a hypocrite, heretic, and atheist.

To Mästlin he wrote:--"What is to be done? I think we should imitate

the Pythagoreans, communicate our discoveries _privatim_, and be silent

in public, that we may not die of hunger. The guardians of the Holy

Scriptures make an elephant of a gnat. To avoid the hatred against

novelty, I represented my discovery to the Rector of the University as

a thing already observed by the ancients; but he made its antiquity a

greater charge against it than he could have made of its novelty."

And, indeed, the devotion to truth in that age, as in others, required

an heroic heart. Copernicus kept back the publication of his "De

Revolutionibus Orbium Caeslestium" for thirty-six years, and received a

copy of it only on his death-bed. Galileo tasted the sweets of the

Inquisition. Tycho Brahe was exiled. And Kepler himself was persecuted

all his life, hounded from city to city. And yet the sixteenth century

will ever be memorable in the history of the human mind. The breaking

down of external authority, the uprise of the spirit of inquiry, of

skepticism, and the splendid scientific conquests that came in

consequence, inaugurated a mighty movement which separates the present

promises of mankind from all past periods by an interval so vast as to

make it not merely a great historical development, but the very birth

of humanity. While Tycho Brahe, at the age of fifty-four, was making

his memorable observations at Prague, Kepler, at the age of thirty, was

applying his fiery mind to the determination of the orbit of Mars, and

Galileo, at thirty-six, was bringing his telescope to the revelation of

new celestial intervals and orbs. Within the succeeding century Huygens

made the application of the pendulum to clocks; Napier invented

Logarithms; Descartes and Galileo created the analysis of curves, and

the science of Dynamics; Leibnitz brought the Differential Calculus;

Newton decomposed a ray of light, and synthesized Kepler's Laws into

the theory of Universal Gravitation.

Into this age, when the Old and New met face to face, came the

questioning and quenchless spirit of Kepler. Born into an age of

adventure, this new Prometheus, this heaven-scaler, matched it with an

audacity to lift it to new reaches of realization.

A singular _naiveté_, too, marked this august soul. He has the

frankness of Montaigne or Jean Jacques. He used to accuse himself of

gabbling in mathematics,--"_in re mathematica loquax_,"--and claimed to

speak with German freedom,--"_scripsi haec, homo Germanicus, more et

libertate Germanica_." He marries far and near, brings planetary

eclipses into conjunction with pecuniary penumbras, and his treatise on

the perturbations of Mars reveals equal perturbations in his domestic

economy. It may be to this candor, this _gemüth_, that we are to

ascribe the powerful personal magnetism he exercises in common with

Rousseau, Rabelais, and other rich and ingenuous natures. Who would be

otherwise than frank, when frankness has this power to captivate? The

excess of this influence appears in the warmth betrayed by writers over

their favorite. The cool-headed Delambre, in his "Histoire de

l'Astronomie," speaks of Kepler with the heat of a pamphleteer, and

cannot repress a frequent sneer at his contemporary, Galileo. We know

the splendor of the Newtonian synthesis; yet we do not find ourselves

affected by Newton's character or discoveries. He touches us with the

passionless love of a star.

Kepler puts the same _naiveté_ into his speculative activity, with a

subtile anatomy laying bare the _metaphysique_ of his science. It was

his habit to illumine his discoveries with an exhibition of the path

that led to them, regarding the method as equally important with the

result,--a principle that has acquired canonical authority in modern

scientific research. "In what follows," writes he, introducing a long

string of hypotheses, the fallacy of which he had already discovered,

"let the reader pardon my credulity, whilst working out all these

matters by my own ingenuity. For it is my opinion that the occasions by

which men have acquired a knowledge of celestial phenomena are not less

admirable than the discoveries themselves." His tentatives, failures,

leadings, his glimpses and his glooms, those aberrations and guesses

and gropings generally so scrupulously concealed, he exposes them all.

From the first flashing of a discovery, through years of tireless toil,

to when the glorious apparition emerges full-orbed and resplendent, we

follow him, becoming party to the process, and sharing the ejaculations

of exultation that leap to his lips. Seventeen years were required for

the discovery of the harmonic law, that the squares of the times of the

planetary revolutions are proportional to the cubes of their mean

distances; and no tragedy ever equalled in affecting intensity the

account he has written of those Promethean years. What rays does he let

into the subtile paths where the spirit travels in its interrogations

of Nature! We should say there was more of what there is of essential

in metaphysics, more of the structural action of the human mind, in his

books, than in the concerted introspection of all the psychologists.

One sees very well that a new astronomy was predicted in the build of

that sky-confronting mind; for harmonic ratios, laws, and rhymes played

in his spheral soul, galaxies and gravitations stretched deeper within,

and systems climbed their flaming ecliptic.

The highest problem of Science is the problem of Method. Hitherto man

has worked on Nature only piecemeal. The understanding and the

logic-faculty are allowed to usurp the rational and creative powers.

One would say that scientists systematically shut themselves out of

three-fourths of their minds, and the English have been insane on

Induction these two hundred years. This unholy divorce has, as it

always must do, brought poverty and impotence into the sciences, many

of which stand apart, stand haggard and hostile, accumulations of

incoherent facts, inhospitable, dead.

It is when contemplated in its historic bearings, as an education of

the faculties of man, that the emphasis that has been placed on special

scientific methods discloses its significance. The speculative

synthesis of Greek and Alexandrine Science was a superb training in

Deduction,--in the descent from consciousness to Nature. Abstracted

from its relations with reality, the scholasticism of the Middle Ages

pushed Deduction to mania and moonshine. Then it was, that, in the

sixteenth and seventeenth centuries, the Occidental mind, astir under

the oceanic movements of the modern, arose to break the spell of

scholasticism that had fettered and frozen the intellect of man. An

all-invading spirit of inquiry, analysis, skepticism, became rife. An

unappeasable hunger for facts, facts, facts, took possession of the

general intellect. It was felt that abstraction was disease, was

death,--that speculation had to be vitalized and enriched from

experience and experiment. This tendency was inevitable and sublime, no

doubt. But it remains for modern times to emulate Nature and carry on

analysis and synthesis at once. A great discovery is the birth of the

whole soul in its creative activity. Induction becomes fruitful only

when married to Deduction. It is those luminous intuitions that light

along the path of discovery that give the eye and animus to

generalization. Science must be open to influx and new beneficent

affections and powers, and so add fleet wings to the mind in its

exploration of Nature.

In Kepler was the perfect realization of the highest mission of Method.

Powerfully deductive in the structure of his intellect, nourished on

the divine bread of Plato and the Mystics, he yet united to these a

Baconian breadth of practical power. Years before the publication of

the "Novum Organum," he gave, in his "Commentaries on the Motions of

Mars," a specimen of the logic of Induction whose circular sweep has

never been matched. Prolific in the generation of hypotheses, he was

yet remorseless in bringing them to the test of experiment. "Hypotheses

which are not founded in Nature please me not," wrote he,--as Newton

inscribed "_Hypotheses non fingo_" on the "Principia." Surely never was

such heroic self-denial. Centurial vigils of baffling calculations

--(remember, there was then little Algebra, and neither Calculus

nor Logarithms)--were sacrificed without a regret except for

the time expended, his tireless intellect pressing on to new heights of

effort. His first work, the "Mysterium Cosmographicum," is the record

of a splendid blunder that cost him five years' toil, and he spent ten

years of fruitless and baffled effort in the deduction of the laws of

areas and orbital ellipticity.

But this audacious diviner knew well the use of Hypothesis, and he

applied it as an instrument of investigation as it had never been

applied before. The vast significance of Hypothesis in the theory of

Scientific Method has never been recognized. It would be a good piece

of psychology to explore the principles of this subtile mental power,

and might go far to give us a philosophy of Anticipation. The men of

facts, men of the understanding, observers,--as we might

suppose,--universally show a disposition to shun theorizing, as opposed

to the exactness of demonstrative science. And yet it is quite certain,

that, in proportion as one rises to a more liberal apprehension, the

immense provisional power of speculative ideas becomes apparent.

Laplace asserted that no great discovery was ever made without a great

guess; and long before, Plato had intimated of these "sacred suspicions

of truth," that descend dawn-like on the mind, sublime premonitions of

beautiful gates of laws. It is these launching tentatives which bring

phenomena to interior and metaphysical tests and bear the mind

swift-winged to Nature. Of course, there are various kinds of

conjecture, and its value will depend on the brain from which it

departs. But a powerful spirit will justify Hypothesis by the high

functions to which he puts it. His guesses are not for nothing. Many

and long processes go to them.--The inexhaustible fertility displayed

by Kepler is a psychologic marvel. He had that subtile chemistry that

turns even failures to account, consumes them in its flaming ascent to

new reaches. After years of labor on his theory of Mars, he found it

failed in application to latitudes and longitudes "out of opposition."

Remorselessly he let his hypothesis go, and drew from his failure an

important inference, the first step towards emancipation from the

ancient prejudice of uniform, circular motion.

Such a genius for Analogy the world never before saw. The perception of

similitude, of correspondence, shot perpetual and prophetic in this

man's glances. To him had been opened the subtile secret, key to

Nature, that Man and the Universe are built after one pattern, and he

had faith to believe that the laws of his mind would unlock the

phenomena of the world.

The law of Analogy flows from the inherent harmonies of Nature. Of this

wise men have ever been intuitive. The eldest Scriptures express it. It

is in the Zend-Avesta, primal Japhetic utterance. It vivified that

subtile Egyptian symbolism. The early Greeks and the Mystics of

Alexandria knew it. Jamblicus reports of Pythagoras, that "he did not

procure for himself a thing of this kind through instruments or the

voice, but, by employing a certain inevitable divinity, and which it is

difficult to apprehend, he extended his ears and fixed his intellect in

the sublime symphonies of the world,--he alone hearing and

understanding, as it appears, the universal harmony and consonance of

the spheres and the stars that are moved through them, and which

produce a fuller and more intense melody than anything effected by

mortal sounds."

From the sublime intuitions of the harmonies of Nature and the unity of

the Universe unfold the bright doctrines of Series and Degrees, of

Correspondence, of Similitude. On these thoughts all wise spirits have

fed. Indeed, you can hardly say they were ever absent. They are of

those flaming thoughts the soul projects, splendid prophecies that

become the light of all our science and all our day. Plato formulated

these laws. Two thousand years after him, the cosmic brain of

Swedenborg traced their working throughout the universal economies of

matter and spirit, and Fourier endeavored to translate them into axioms

of a new social organization.

These doctrines were ever present to the mind of Kepler; and to what

fruitful account he turned Analogy as a means of inductive speculation

his wonderful anatomy of his discoveries reveals. He fed on the

harmonies of the universe. He has it, that "harmony is the perfection

of relations." The work of his mature intellect was the "Harmonices

Mundi," (Harmonies of the World,) in which many of the sublime leadings

of Modern Science, as the Correlation of Sounds and Colors, the

Significance of Musical Chords, the Undulatory Theory, etc., are

prefigured. We must account him one of the chief of those prophetic

spirits who, by attempting to give phenomena a necessary root in ideas,

have breathed into Science a living soul. The new Transcendental

Anatomy,--the doctrine of Homologies,--the Embryologic scheme,

revealing that all animate forms are developed after one

archetype,--the splendid Nebular guess of Laplace,--the thought of the

Metamorphosis of Plants,--the attempts at profounder explanations of

Light and Colors,--the rising transcendentalism of Chemistry,--the

magnificent intuition of Correspondence, showing a grand unity of

design in the nodes of shells, the phyllotaxism of plants, and the

serialization of planets,--are all signs of the presence of a spirit

that is to usher in a new dispensation of Science, fraught with

divinest messages to the head and heart of man.

Kepler regarded Analogy as the soul of Science, and he has made it an

instrument of prophecy and power. Thus, he inferred from Analogy that

the sun turned on its axis, long before Galileo was able to direct his

telescope to the solar spots and so determine this rotation as an

actual fact. He anticipated a planet between Mars and Jupiter too small

to be seen; and his inference that the obliquity of the ecliptic was

decreasing, but would, after a long-continued diminution, stop, and

then increase again, afterwards acquired the sanction of demonstration.

A like instance of anticipation is afforded in the beautiful experiment

of the freely-suspended ball revolving in an ellipse under the combined

influence of the central and tangential forces, which Jeremiah Horrocks

devised, when pursuing Kepler's theory of planetary motion,--his

intuition being, that the motions of the spheres might be represented

by terrestrial movements. We may mention the observation which the

ill-starred Horrocks makes, in a letter,[1] on the occasion of this

experiment, as one of the sublimities of Science:--"It appears to me,

however, that I have fallen upon the true theory, and that it admits of

being illustrated by natural movements on the surface of the earth; for

Nature everywhere acts according to a uniform plan, and the harmony of

creation is such that small things constitute a faithful type of

greater things." Another instance is afforded in the grand intuition of

Oken, who, when rambling in the Hartz Mountains, lit upon the skull of

a deer, and saw that the cranium was but an expansion of vertebrae, and

that the vertebra is the theoretical archetype of the entire osseous

framework,--the foundation of modern Osteology. And still another is

the well-known instance of the change in polarization predicted by

Fresnel from the mere interpretation of an algebraic symbol. This

prophetic insight is very sublime, and opens up new spaces in man.

[Footnote 1: _Correspondence,_ 1637]

Of the discoveries of Kepler, we can here have to do with their

universal and humanitary bearings alone. It is to be understood,

however, that the three grand sweeps of Deduction which we call

Kepler's Laws formed the foundation of the higher conception of

astronomy, that is, the dynamical theory of astronomical phenomena, and

prepared the way for the "Mécanique Céleste." Whewell, the learned

historian of the Sciences, speaks of them as "by far the most

magnificent and most certain train of truths which the whole expanse of

human knowledge can show"; and Comte declares, that "history tells of

no such succession of philosophical efforts as in the case of Kepler,

who, after constituting Celestial Geometry, strove to pursue that

science of Celestial Mechanics which was by its very nature reserved

for a future generation." These laws are, first, the law of the

velocities of the planets; second, the law of the elliptic orbit of the

planets; and, third, the harmonic law, that the squares of the times of

the planetary revolutions are proportional to the cubes of their mean

distances from the sun. They compass the whole sweep of Celestial

Geometry, and stamp their seer as unapproachably the greatest of

astronomers, as well as one of the chief benefactors of mankind.

The announcement of Kepler's first two laws was made in his New

Astronomy,--"Astronomia Nova, seu Physica Caelestis, tradita

Commentariis de Motibus Stellae Martis: Ex Observationibus G.V.

Tychonis Brahe." Folio. Prague: 1609. This he published in his

thirty-eighth year. The title he gave to this work, "Celestial

Physics," must ever be regarded as a stroke of philosophical genius; it

is the prediction of Newton and Laplace, and prefigures the path on

which astronomical discovery has advanced these two hundred and fifty

years.

An auspicious circumstance conspired to forward the astronomical

discoveries of Kepler. Invited to Prague in 1600 by Tycho Brahe, as

Assistant Royal Astronomer, he had access to the superb series of

observations which Tycho had been accumulating for twenty-five years.

Endowed with a genius for observation unsurpassed in the annals of

science, the noble Dane had obtained a grant from the king of Denmark

of the island of Hven, at the mouth of the Baltic. Here he erected a

magnificent observatory, which he named _Uranienborg_, City of the

Heavens. This he fitted up with a collection of instruments of hitherto

unapproached size and perfection, and here, for twenty years, he

pursued his observations. Thus it was that Kepler, himself a poor

observer, found his complement in one who, without any power of

constructive generalization, was yet the possessor of the richest

series of astronomical observations ever made. From this admirable

conjunction admirable realizations were to be expected. And, indeed,

the "Astronomia Nova" presents an unequalled illustration of

observation vivified by theory, and theory tested and fructified by

observation.

To appreciate the significance of the discovery of the elliptical orbit

of the planets, it is necessary to understand the complicated confusion

that prevailed in the conception of planetary motions. The primal

thought was that the motions of the planets were uniform and circular.

This intuition of circular orbits was a happy one, and was, perhaps,

necessitated by the very structure of the human mind. The sweeping and

centrifugal soul, darting manifold rays of equal reach, realizes the

conception of the circle, that is, a figure all of whose radii are

equidistant from a central point. But this conception of the circle

afterwards came to acquire superstitious tenacity, being regarded as

the perfect form, and the only one suitable for such divine natures as

the stars, and was for two thousand years an impregnable barrier to the

progress of Astronomy. To account for every new appearance, every

deviation from circular perfection, a new cycloid was supposed, till

all the simplicity of the original hypothesis was lost in a

complication of epicycles:--

"The sphere,

With centric and eccentric scribbled o'er,

Cycle and epicycle, orb in orb."

By the end of the sixteenth century the number of circles supposed

necessary for the seven stars then known amounted to seventy-four,

while Tycho Brahe was discovering more and more planetary movements for

which these circles would not account.

To push aside forever this complicated chaos and evoke celestial order

and harmony, came Kepler. Long had the sublime intuition possessed him,

that numerical and geometrical relations connect the distances, times,

and revolutions of the planets. He began his studies on the planet

Mars,--a fortunate choice, as the marked eccentricity of that planet

would afford ready suggestions and verifications of the true law of

irregularity, and on which Tycho had accumulated copious data. It had

long been remarked that the angular velocity of each planet increases

constantly in proportion as the body approaches its centre of motion;

but the relation between the distance and the velocity remained wholly

unknown. Kepler discovered it by comparing the maximum and minimum of

these quantities, by which their relation became more sensible. He

found that the angular velocities of Mars at its nearest and farthest

distances from the sun were in inverse proportion to the squares of the

corresponding distances. This law, deduced, was the immediate path to

the law of orbital ellipticity. For, on attempting to apply his

newly-discovered law to Mars, on the old assumption that its orbit was

a circle, he soon found that the results from the combination of the

two principles were such as could not be reconciled with the places of

Mars observed by Tycho. In this dilemma, finding he must give up one or

the other of these principles, he first proposed to sacrifice his own

theory to the authority of the old system,--a memorable example of

resolute candor. But, after indefatigably subjecting it to crucial

experiment, he found that it was the old hypothesis, and not the new

one, that had to be sacrificed.[1] If the orbit was not a circle, what,

then, was it? By a happy stroke of philosophical genius he lit on the

ellipse. On bringing his hypothesis to the test of observation, he

found it was indeed so; and rising from the case of Mars to universal

statement, he generalized the law, that the planetary orbits are

elliptical, having the sun for their common focus.

[Footnote 1: ROBERT SMALL: _Astronomical Discoveries of Kepler_.]

Kepler had now determined the course of each planet. But there was no

known relation between the distances and times; and the evolution of

some harmony between these factors was to him an object of the greatest

interest and the most restless curiosity. Long he dwelt in the dream of

the Pythagorean harmonies. Then he essayed to determine it from the

regular geometrical solids, and afterwards from the divisions of

musical chords. Over twenty years he spent in these baffled efforts. At

length, on the 8th of March, 1618, it occurred to him, that, instead of

comparing the simple times, he should compare the numbers expressing

the similar powers, as squares, cubes, etc.; and lastly, he made the

very comparison on which his discovery was founded, between the squares

of the times and the cubes of the distances. But, through some error of

calculation, no common relation was found between them. Finding it

impossible, however, to banish the subject from his thoughts, he tells

us, that on the 8th of the following May he renewed the last of these

comparisons, and, by repeating his calculations with greater care,

found, with the highest astonishment and delight, that the ratio of the

squares of the periodical times of any two planets was constantly and

invariably the same with the ratio of the cubes of their mean distances

from the sun. Then it was that he burst forth in his memorable

rhapsody:--"What I prophesied twenty-two years ago, as soon as I

discovered the five solids among the heavenly orbits,--what I firmly

believed long before I had seen Ptolemy's harmonics,--what I had

promised my friends in the title of this book, which I named before I

was sure of my discovery,--what sixteen years ago I urged as a thing to

be sought,--that for which I joined Tycho Brahe, for which I settled in

Prague, for which I have devoted the best part of my life to

astronomical contemplation,--at length I have brought to light, and

have recognized its truth beyond my most sanguine expectations. It is

now eighteen months since I got the first glimpse of light, three

months since the dawn, very few days since the unveiled sun, most

admirable to gaze upon, burst out upon me. Nothing holds me; I will

indulge in my sacred fury; I will triumph over mankind by the honest

confession, that I have stolen the golden vases of the Egyptians to

build up a tabernacle for my God far away from the confines of Egypt.

If you forgive me, I rejoice; if you are angry, I can bear it: the die

is cast; the book is written, to be read either now or by posterity, I

care not which: it may well wait a century for a reader, as God has

waited six thousand years for an observer!"

These laws have, no doubt, a universal significance, and may be

translated into problems of life. For, after the farthest sweep of

Induction, a question yet remains to be asked: Whence comes the power

to perceive a law? Whence that subtile correspondence and

consanguinity, that the laws of man's mental structure tally with the

phenomena of the universe? To this problem of problems our science as

yet affords but meagre answers. It seems though, so far in the history

of humanity, it had been but given man to recognize this truth as a

splendid idealism, without the ability to make it potential in his

theory of the world. Yet what a key to new and beautiful gates of laws!

"Who can be sure to find its true degree,

_Magister magnus in igne_ shall he be."

Antique and intuitive nations--Indians, Egyptians, Greeks--sought a

solution of this august mystery in the doctrines of Transmigration and

Anamnesis or Reminiscence. Nothing is whereto man is not kin. He knows

all worlds and histories by virtue of having himself travelled the

mystic spiral descent. Awaking through memory, the processes of his

mind repeat the processes of the visible Kosmos. His unfolding is a

hymn of the origination of the world.

Nature and man having sprung from the same spiritual source, a perfect

agreement subsists between the phenomena of the world and man's

mentality. This is necessary to the very conception of Science. If the

laws of reason did not exist in Nature, we should vainly attempt to

force them upon her: if the laws of Nature did not exist in our reason,

we should not be able to comprehend them.[1] There is a saying reported

of Zoroaster, and, coming from the deeps of fifty centuries, still

authentic and intelligible, that "the congruities of material forms to

the laws of the soul are divine allurements." Ever welcome is the

perception of this truth,--as the sublime audacity of Paracelsus, that

"those who would understand the course of the heavens above must first

of all recognize the heaven in man"; and the affirmation, that "the

laws of Nature are the same as the thoughts within us: the laws of

motion are such as are required by our understanding." It remains to

say that Kepler, too, had intuition of this lofty thought. At the

conclusion of his early work, "The Prodromus Dissertationum

Cosmographicarum," he wrote,--"As men enjoy dainties at the dessert, so

do wise souls gain a taste for heavenly things when they ascend from

their college to the universe and there look around them. Great Artist

of the World! I look with wonder on the works of Thy hands, constructed

after five regular forms, and in the midst the sun, the dispenser of

light and life. I see the moon and stars strewn over the infinite field

of space. Father of the World! what moved Thee thus to exalt a poor, weak

little creature of earth so high that he stands in light a far-ruling

king, almost a god?--_for he thinks Thy thoughts after Thee_."

[Footnote 1: OERSTED: _Soul in Nature._]

It is impossible not to feel freer at the accession of so much power as

these laws bring us. They carry farther on the bounds of humanity. The

stars are the eternal monitions of spirituality. Who can estimate how

much man's thoughts have been colored by these golden kindred? It seems

as though it were but required to show man space,--space, space,

space,--there is that in him will fill and pass it. There is that in

the celestial prodigies--in gulfs of Time and Space--that seems to mate

the greed of the soul. There is that greed in the soul to pass through

worlds and ages,--through growths, griefs, desires, processes,

spheres,--to travel the endless highways,--to pass and resume again. O

Heavens, you are but a splendid fable of the elder mind! Centripetal

and centrifugal are in man, too, and primarily; and an aspiring soul

will ascend into the sweeps and circles, and pass swift and devouring

through baffling intervals and steep-down strata of galaxies and stars.

The thought that overarches the centuries with firmamental sweep is the

thought of the Ensemble. To this all has led along,--but the

disclosures of Astronomy especially. The discovery of the earth's

revolution, at once transporting the stars to distances outside of all

telluric connection, broke the old spell, and replaced the petty

provincialism of the earth as the All-Centre by the vast, sublime

conception of the Universe. Laplace has pointed this out, showing how

to the fantastic and enervating notion of a universe arranged for man

has succeeded the sound and vivifying thought of man discovering, by a

positive exercise of his intelligence, the general laws of the world,

so as to be able to modify them for his own good, within certain

limits. Dawning prophetic on modern times, the thought of the Ensemble

holds the seeds of new humanitary growths. This is the vast similitude

that binds together the ages,--that balances creeds, colors, eras.

Through Nature, man, forms, spirit, the eternal conspiracy works and

weaves. This is the water of spirituality. All is bound up in the

Divine Scheme. The Divine Scheme encloses all.