Galileo by the Inquisitor General, and it was accordingly sent to the
press. It might be thought that the anxieties of the astronomer
about his book would then have terminated. As a matter of fact, they
had not yet seriously begun. Riccardi, the Master of the Sacred
Palace, having suddenly had some further misgivings, sent to Galileo
for the manuscript while the work was at the printer's, in order that
the doctrine it implied might be once again examined. Apparently,
Riccardi had come to the conclusion that he had not given the matter
sufficient attention, when the authority to go to press had been
first and, perhaps, hastily given. Considerable delay in the issue
of the book was the result of these further deliberations. At last,
however, in June, 1632, Galileo's great work, "The Dialogue of the
two Systems," was produced for the instruction of the world, though
the occasion was fraught with ruin to the immortal author.
[PLATE: FACSIMILE SKETCH OF LUNAR SURFACE BY GALILEO.]
The book, on its publication, was received and read with the greatest
avidity. But presently the Master of The Sacred Palace found reason
to regret that he had given his consent to its appearance. He
accordingly issued a peremptory order to sequestrate every copy in
Italy. This sudden change in the Papal attitude towards Galileo
formed the subject of a strong remonstrance addressed to the Roman
authorities by the Grand Duke of Tuscany. The Pope himself seemed to
have become impressed all at once with the belief that the work
contained matter of an heretical description. The general
interpretation put upon the book seems to have shown the authorities
that they had mistaken its true tendency, notwithstanding the fact
that it had been examined again and again by theologians deputed for
the duty. To the communication from the Grand Duke the Pope returned
answer, that he had decided to submit the book to a congregation of
"learned, grave, and saintly men," who would weigh every word in it.
The views of his Holiness personally on the subject were expressed in
his belief that the Dialogue contained the most perverse matter that
could come into a reader's hands.
The Master of the Sacred Palace was greatly blamed by the authorities
for having given his sanction to its issue. He pleaded that the book
had not been printed in the precise terms of the original manuscript
which had been submitted to him. It was also alleged that Galileo
had not adhered to his promise of inserting properly the arguments
which the Pope himself had given in support of the old and orthodox
view. One of these had, no doubt, been introduced, but, so far from
mending Galileo's case, it had made matters really look worse for the
poor philosopher. The Pope's argument had been put into the mouth of
one of the characters in the Dialogue named "Simplicio." Galileo's
enemies maintained that by adopting such a method for the expression
of his Holiness's opinion, Galileo had intended to hold the Pope
himself up to ridicule. Galileo's friends maintained that nothing
could have been farther from his intention. It seems, however,
highly probable that the suspicions thus aroused had something to say
to the sudden change of front on the part of the Papal authorities.
On 1st October, 1632, Galileo received an order to appear before the
Inquisition at Rome on the grave charge of heresy. Galileo, of
course, expressed his submission, but pleaded for a respite from
compliance with the summons, on the ground of his advanced age and
his failing health. The Pope was, however, inexorable; he said that
he had warned Galileo of his danger while he was still his friend.
The command could not be disobeyed. Galileo might perform the
journey as slowly as he pleased, but it was imperatively necessary
for him to set forth and at once.
On 20th January, 1633, Galileo started on his weary journey to Rome,
in compliance with this peremptory summons. On 13th February he was
received as the guest of Niccolini, the Tuscan ambassador, who had
acted as his wise and ever-kind friend throughout the whole affair.
It seemed plain that the Holy Office were inclined to treat Galileo
with as much clemency and consideration as was consistent with the
determination that the case against him should be proceeded with to
the end. The Pope intimated that in consequence of his respect for
the Grand Duke of Tuscany he should permit Galileo to enjoy the
privilege, quite unprecedented for a prisoner charged with heresy, of
remaining as an inmate in the ambassador's house. He ought,
strictly, to have been placed in the dungeons of the Inquisition.
When the examination of the accused had actually commenced, Galileo
was confined, not, indeed, in the dungeons, but in comfortable rooms
at the Holy Office.
By the judicious and conciliatory language of submission which
Niccolini had urged Galileo to use before the Inquisitors, they were
so far satisfied that they interceded with the Pope for his release.
During the remainder of the trial Galileo was accordingly permitted
to go back to the ambassador's, where he was most heartily welcomed.
Sister Maria Celeste, evidently thinking this meant that the whole
case was at an end, thus expresses herself:--
"The joy that your last dear letter brought me, and the having to
read it over and over to the nuns, who made quite a jubilee on
hearing its contents, put me into such an excited state that at last
I got a severe attack of headache."
In his defence Galileo urged that he had already been acquitted in
1616 by Cardinal Bellarmine, when a charge of heresy was brought
against him, and he contended that anything he might now have done,
was no more than he had done on the preceding occasion, when the
orthodoxy of his doctrines received solemn confirmation. The
Inquisition seemed certainly inclined to clemency, but the Pope was
not satisfied. Galileo was accordingly summoned again on the 21st
June. He was to be threatened with torture if he did not forthwith
give satisfactory explanations as to the reasons which led him to
write the Dialogue. In this proceeding the Pope assured the Tuscan
ambassador that he was treating Galileo with the utmost consideration
possible in consequence of his esteem and regard for the Grand Duke,
whose servant Galileo was. It was, however, necessary that some
exemplary punishment be meted out to the astronomer, inasmuch as by
the publication of the Dialogue he had distinctly disobeyed the
injunction of silence laid upon him by the decree of 1616. Nor was
it admissible for Galileo to plead that his book had been sanctioned
by the Master of the Sacred College, to whose inspection it had been
again and again submitted. It was held, that if the Master of the
Sacred College had been unaware of the solemn warning the philosopher
had already received sixteen years previously, it was the duty of
Galileo to have drawn his attention to that fact.
On the 22nd June, 1633, Galileo was led to the great hall of the
Inquisition, and compelled to kneel before the cardinals there
assembled and hear his sentence. In a long document, most
elaborately drawn up, it is definitely charged against Galileo that,
in publishing the Dialogue, he committed the essentially grave error
of treating the doctrine of the earth's motion as open to
discussion. Galileo knew, so the document affirmed, that the Church
had emphatically pronounced this notion to be contrary to Holy Writ,
and that for him to consider a doctrine so stigmatized as having any
shadow of probability in its favour was an act of disrespect to the
authority of the Church which could not be overlooked. It was also
charged against Galileo that in his Dialogue he has put the strongest
arguments into the mouth, not of those who supported the orthodox
doctrine, but of those who held the theory as to the earth's motion
which the Church had so deliberately condemned.
After due consideration of the defence made by the prisoner, it was
thereupon decreed that he had rendered himself vehemently suspected
of heresy by the Holy Office, and in consequence had incurred all the
censures and penalties of the sacred canons, and other decrees
promulgated against such persons. The graver portion of these
punishments would be remitted, if Galileo would solemnly repudiate
the heresies referred to by an abjuration to be pronounced by him in
the terms laid down.
At the same time it was necessary to mark, in some emphatic manner,
the serious offence which had been committed, so that it might serve
both as a punishment to Galileo and as a warning to others. It was
accordingly decreed that he should be condemned to imprisonment in
the Holy Office during the pleasure of the Papal authorities, and
that he should recite once a week for three years the seven
Penitential Psalms.
Then followed that ever-memorable scene in the great hall of the
Inquisition, in which the aged and infirm Galileo, the inventor of
the telescope and the famous astronomer, knelt down to abjure before
the most eminent and reverend Lords Cardinal, Inquisitors General
throughout the Christian Republic against heretical depravity. With
his hands on the Gospels, Galileo was made to curse and detest the
false opinion that the sun was the centre of the universe and
immovable, and that the earth was not the centre of the same, and
that it moved. He swore that for the future he will never say nor
write such things as may bring him under suspicion, and that if he
does so he submits to all the pains and penalties of the sacred
canons. This abjuration was subsequently read in Florence before
Galileo's disciples, who had been specially summoned to attend.
It has been noted that neither on the first occasion, in 1616, nor on
the second in 1633, did the reigning Pope sign the decrees concerning
Galileo. The contention has accordingly been made that Paul V. and
Urban VIII. are both alike vindicated from any technical
responsibility for the attitude of the Romish Church towards the
Copernican doctrines. The significance of this circumstance has been
commented on in connection with the doctrine of the infallibility of
the Pope.
We can judge of the anxiety felt by Sister Maria Celeste about her
beloved father during these terrible trials. The wife of the
ambassador Niccolini, Galileo's steadfast friend, most kindly wrote
to give the nun whatever quieting assurances the case would permit.
There is a renewed flow of these touching epistles from the daughter
to her father. Thus she sends word--
"The news of your fresh trouble has pierced my soul with grief all
the more that it came quite unexpectedly."
And again, on hearing that he had been permitted to leave Rome,
she writes--
"I wish I could describe the rejoicing of all the mothers and sisters
on hearing of your happy arrival at Siena. It was indeed most
extraordinary. On hearing the news the Mother Abbess and many of the
nuns ran to me, embracing me and weeping for joy and tenderness."
The sentence of imprisonment was at first interpreted leniently by
the Pope. Galileo was allowed to reside in qualified durance in the
archbishop's house at Siena. Evidently the greatest pain that he
endured arose from the forced separation from that daughter, whom he
had at last learned to love with an affection almost comparable with
that she bore to him. She had often told him that she never had any
pleasure equal to that with which she rendered any service to her
father. To her joy, she discovers that she can relieve him from the
task of reciting the seven Penitential Psalms which had been imposed
as a Penance:--
"I began to do this a while ago," she writes, "and it gives me much
pleasure. First, because I am persuaded that prayer in obedience to
Holy Church must be efficacious; secondly, in order to save you the
trouble of remembering it. If I had been able to do more, most
willingly would I have entered a straiter prison than the one I live
in now, if by so doing I could have set you at liberty."
[PLATE: CREST OF GALILEO'S FAMILY.]
Sister Maria Celeste was gradually failing in health, but the great
privilege was accorded to her of being able once again to embrace her
beloved lord and master. Galileo had, in fact, been permitted to
return to his old home; but on the very day when he heard of his
daughter's death came the final decree directing him to remain in his
own house in perpetual solitude.
Amid the advancing infirmities of age, the isolation from friends,
and the loss of his daughter, Galileo once again sought consolation
in hard work. He commenced his famous dialogue on Motion. Gradually,
however, his sight began to fail, and blindness was at last added to
his other troubles. On January 2nd, 1638, he writes to Diodati:--
"Alas, your dear friend and servant, Galileo, has been for the last
month perfectly blind, so that this heaven, this earth, this universe
which I by my marvellous discoveries and clear demonstrations have
enlarged a hundred thousand times beyond the belief of the wise men
of bygone ages, henceforward is for me shrunk into such a small space
as is filled by my own bodily sensations."
But the end was approaching--the great philosopher, was attacked by
low fever, from which he died on the 8th January, 1643.
KEPLER.
While the illustrious astronomer, Tycho Brahe, lay on his death-bed,
he had an interview which must ever rank as one of the important
incidents in the history of science. The life of Tycho had been
passed, as we have seen, in the accumulation of vast stores of
careful observations of the positions of the heavenly bodies. It was
not given to him to deduce from his splendid work the results to
which they were destined to lead. It was reserved for another
astronomer to distil, so to speak, from the volumes in which Tycho's
figures were recorded, the great truths of the universe which those
figures contained. Tycho felt that his work required an interpreter,
and he recognised in the genius of a young man with whom he was
acquainted the agent by whom the world was to be taught some of the
great truths of nature. To the bedside of the great Danish
astronomer the youthful philosopher was summoned, and with his last
breath Tycho besought of him to spare no labour in the performance of
those calculations, by which alone the secrets of the movements of
the heavens could be revealed. The solemn trust thus imposed was
duly accepted, and the man who accepted it bore the immortal name of
Kepler.
Kepler was born on the 27th December, 1571, at Weil, in the Duchy of
Wurtemberg. It would seem that the circumstances of his childhood
must have been singularly unhappy. His father, sprung from a
well-connected family, was but a shiftless and idle adventurer; nor
was the great astronomer much more fortunate in his other parent. His
mother was an ignorant and ill-tempered woman; indeed, the
ill-assorted union came to an abrupt end through the desertion of the
wife by her husband when their eldest son John, the hero of our
present sketch, was eighteen years old. The childhood of this lad,
destined for such fame, was still further embittered by the
circumstance that when he was four years old he had a severe attack
of small-pox. Not only was his eyesight permanently injured, but
even his constitution appears to have been much weakened by this
terrible malady.
It seems, however, that the bodily infirmities of young John Kepler
were the immediate cause of his attention being directed to the
pursuit of knowledge. Had the boy been fitted like other boys for
ordinary manual work, there can be hardly any doubt that to manual
work his life must have been devoted. But, though his body was
feeble, he soon gave indications of the possession of considerable
mental power. It was accordingly thought that a suitable sphere for
his talents might be found in the Church which, in those days, was
almost the only profession that afforded an opening for an
intellectual career. We thus find that by the time John Kepler was
seventeen years old he had attained a sufficient standard of
knowledge to entitle him to admission on the foundation of the
University at Tubingen.
In the course of his studies at this institution he seems to have
divided his attention equally between astronomy and divinity. It not
unfrequently happens that when a man has attained considerable
proficiency in two branches of knowledge he is not able to see very
clearly in which of the two pursuits his true vocation lies. His
friends and onlookers are often able to judge more wisely than he
himself can do as to which of the two lines it would be better for
him to pursue. This incapacity for perceiving the path in which
greatness awaited him, existed in the case of Kepler. Personally, he
inclined to enter the ministry, in which a promising career seemed
open to him. He yielded, however, to friends, who evidently knew him
better than he knew himself, and accepted in 1594, the important
Professorship of astronomy which had been offered to him in the
University of Gratz.
It is difficult for us in these modern days to realise the somewhat
extraordinary duties which were expected from an astronomical
professor in the sixteenth century. He was, of course, required to
employ his knowledge of the heavens in the prediction of eclipses,
and of the movements of the heavenly bodies generally. This seems
reasonable enough; but what we are not prepared to accept is the
obligation which lay on the astronomers to predict the fates of
nations and the destinies of individuals.
It must be remembered that it was the almost universal belief in
those days, that all the celestial spheres revolved in some
mysterious fashion around the earth, which appeared by far the most
important body in the universe. It was imagined that the sun, the
moon, and the stars indicated, in the vicissitudes of their
movements, the careers of nations and of individuals. Such being the
generally accepted notion, it seemed to follow that a professor who
was charged with the duty of expounding the movements of the heavenly
bodies must necessarily be looked to for the purpose of deciphering
the celestial decrees regarding the fate of man which the heavenly
luminaries were designed to announce.
Kepler threw himself with characteristic ardour into even this
fantastic phase of the labours of the astronomical professor; he
diligently studied the rules of astrology, which the fancies of
antiquity had compiled. Believing sincerely as he did in the
connection between the aspect of the stars and the state of human
affairs, he even thought that he perceived, in the events of his own
life, a corroboration of the doctrine which affirmed the influence of
the planets upon the fate of individuals.
[PLATE: KEPLER'S SYSTEM OF REGULAR SOLIDS.]
But quite independently of astrology there seem to have been many
other delusions current among the philosophers of Kepler's time. It
is now almost incomprehensible how the ablest men of a few centuries
ago should have entertained such preposterous notions, as they did,
with respect to the system of the universe. As an instance of what
is here referred to, we may cite the extraordinary notion which,
under the designation of a discovery, first brought Kepler into
fame. Geometers had long known that there were five, but no more
than five, regular solid figures. There is, for instance, the cube
with six sides, which is, of course, the most familiar of these
solids. Besides the cube there are other figures of four, eight,
twelve, and twenty sides respectively. It also happened that there
were five planets, but no more than five, known to the ancients,
namely, Mercury, Venus, Mars, Jupiter, and Saturn. To Kepler's
lively imaginations this coincidence suggested the idea that the five
regular solids corresponded to the five planets, and a number of
fancied numerical relations were adduced on the subject. The
absurdity of this doctrine is obvious enough, especially when we
observe that, as is now well known, there are two large planets, and
a host of small planets, over and above the magical number of the
regular solids. In Kepler's time, however, this doctrine was so far
from being regarded as absurd, that its announcement was hailed as a
great intellectual triumph. Kepler was at once regarded with
favour. It seems, indeed, to have been the circumstance which
brought him into correspondence with Tycho Brahe. By its means also
he became known to Galileo.
The career of a scientific professor in those early days appears
generally to have been marked by rather more striking vicissitudes
than usually befall a professor in a modern university. Kepler was a
Protestant, and as such he had been appointed to his professorship at
Gratz. A change, however, having taken place in the religious belief
entertained by the ruling powers of the University, the Protestant
professors were expelled. It seems that special influence having
been exerted in Kepler's case on account of his exceptional eminence,
he was recalled to Gratz and reinstated in the tenure of his chair.
But his pupils had vanished, so that the great astronomer was glad to
accept a post offered him by Tycho Brahe in the observatory which the
latter had recently established near Prague.
On Tycho's death, which occurred soon after, an opening presented
itself which gave Kepler the opportunity his genius demanded. He was
appointed to succeed Tycho in the position of imperial mathematician.
But a far more important point, both for Kepler and for science,
was that to him was confided the use of Tycho's observations. It was,
indeed, by the discussion of Tycho's results that Kepler was enabled
to make the discoveries which form such an important part of
astronomical history.
Kepler must also be remembered as one of the first great astronomers
who ever had the privilege of viewing celestial bodies through a
telescope. It was in 1610 that he first held in his hands one of
those little instruments which had been so recently applied to the
heavens by Galileo. It should, however, be borne in mind that the
epoch-making achievements of Kepler did not arise from any telescopic
observations that he made, or, indeed, that any one else made. They
were all elaborately deduced from Tycho's measurements of the
positions of the planets, obtained with his great instruments, which
were unprovided with telescopic assistance.
To realise the tremendous advance which science received from
Kepler's great work, it is to be understood that all the astronomers
who laboured before him at the difficult subject of the celestial
motions, took it for granted that the planets must revolve in
circles. If it did not appear that a planet moved in a fixed circle,
then the ready answer was provided by Ptolemy's theory that the
circle in which the planet did move was itself in motion, so that its
centre described another circle.
When Kepler had before him that wonderful series of observations of
the planet, Mars, which had been accumulated by the extraordinary
skill of Tycho, he proved, after much labour, that the movements of
the planet refused to be represented in a circular form. Nor would
it do to suppose that Mars revolved in one circle, the centre of
which revolved in another circle. On no such supposition could the
movements of the planets be made to tally with those which Tycho had
actually observed. This led to the astonishing discovery of the true
form of a planet's orbit. For the first time in the history of
astronomy the principle was laid down that the movement of a planet
could not be represented by a circle, nor even by combinations of
circles, but that it could be represented by an elliptic path. In
this path the sun is situated at one of those two points in the
ellipse which are known as its foci.
[PLATE: KEPLER.]