Appeared in the souvenir of All India PeopleScience Congress meeting in Bangalore 22-25
Galileo - The father of modern science
Palahalli (P.R.) Vishwanath
Venice is associated with several interesting people. The great sea travels of the late 15th century were triggered essentially by accounts of Marco Polo , the itinerant Venetian traveler of the 12th century. Who can forget Shylock, the Merchant of Venice who became a symbol of oppression? But the most colourful personality was the man who was to usher in the modern era in the history of science. When one goes today to St Marco square in Venice, one can imagine the great Galileo showing off the first practical uses of telescope to the Venetian senate! It was in August of 1609 that the 45 year old professor of Padua took the distinguished members along with the Doge to the tower. There he trained his new instrument on the distant ships: “ The distinguished members did not mind climbing the tower twice just to see ships which were really at 50 miles would appear as near as at 5 miles”. One could sense the enemy ships much faster and thus prepare better for the onslought ! When this military use of the telescope was understood by the Venetians, they tempted Galileo with a bigger salary to stay in Venice!
1564 is
an important year in the history of mankind. It was the time of
Emperor Akbar in India and Queen Elizabeth in England. This was the
year of birth of William Shakespeare in England and Galileo Galilei
in Italy. Five cities were to play an important role in Galileo’s
life : Pisa, Padua, Florence, Venice and Rome. Pisa was where Galileo
was born. Florence was the seat of the powerful Medicis who had
jurisdiction over the university at Pisa. The coastal city Venice had
become prominent since 10th century and was ruled by a
republican set up. Venice , a liberal city state, controlled the
nearby university of Padua. Rome had neither a duke; it was not a
republic either. It was controlled by the defacto ruler of the
Christian world, the Pope of the Roman catholic world. Venice and
Florence had boundaries, but not for the holy Roman empire!
Galileo’s
father Vincento, a musician by profession, wanted Galileo to learn
medicine and sent him to the university at Pisa. May be those were
the days when the 19 year old Galileo sitting in a cathedral and
listening to a boring sermon began staring at the chandelier swinging
from the ceiling of the church. He used his pulse rate to measure the
time taken for the lamp to swing from one direction to the other.
This is where he came up with the great discovery that the duration
was same irrespective of how far the lamp swung. This basic
principle of the pendulum was of later use in the invention of the
clock. The accuracy of clocks before Galileo was about 15 minutes
whereas after him it decreased by a great magnitude to 15 seconds!
He got a
job as a lecturer in the University of Pisa in 1589. Like all old
seats of learning, Pisa also subscribed to trappings of academia. The
lecturers were expected to wear togas (long gowns). He had to leave
the town when he ridiculed that custom with a poem. In 1592 he was
lucky to get a lecturership at the university of Padua where he
stayed for the next 18 years. ‘Ignorance of mechanics is ignorance
of the nature ‘: this had been the admonishment of Aristotle to
scholars. Galileo took it seriously and made great contributions to
the field of mechanics. The Greeks had asked ‘ why does it move’.
But Galileo changed the whole basis of science when he realized that
the right question to ask is ‘ How does it move’?!
We
digress here to look at the birth of an instrument which
revolutionized astronomy. The impact of old age is felt at first by
the eyes. This is when most people start having problems for nearby
objects. The Roman senator Seneca had known that objects appeared
bigger when seen through water. The 13th century British
scientist Roger Bacon did experiments with magnifying glasses and
concluded that they could be used to repair vision. At first these
glasses were worn directly on the nose. These are concave lenses. For
short sighted people , convex lenses were prescribed. The great
Petrarch of 14th century who was responsible for revival
of classical thought expresses annoyance at the fact that he had to
wear glasses!
From
spectacles to telescope was probably an inevitable step. The legend
has it that children playing in a spectacles shoprun by a glass maker
called Lepershey in Holland joined the two types of lenses and thus
was born the telescope. A merchant brought a telescope and tried to
sell it to the Venetian government which invited the professor at
nearby Padua to take a look at it. It was not difficult for Galileo
who was very skilled with his hands to improve the design and
manufacture a better telescope ! Its magnifying power was 9 times the
one offered by the merchant. Later he improved the magnification to
60 ! A new era in astronomy opened up when Galileo turned the
telescope to look at the night sky in 1610 !
In a
matter of just 3 months, from Dec 1609 to Feb 1610) Galileo came up
with 5 great discoveries : With the preface “ I am the first one
to look closely at the wonders of the sky and I thank God for this
great opportunity “the discoveries could be listed (a) MOON :
Just like the earth, moon’s surface also has large ups and downs.
There are no great differences between the earth and the moon. (b)
JUPITER: "On Jan 7th to the east of the
planet, three stars on the same line. – on the next day, the same
three stars, but now on the west side ---may be there is some problem
with Jupiter’s movement – On Jan 10th only 2 stars are
seen – No, there is no problem with Jupiter. The stars are going
round the planet like the planets go round the sun! “ Moon is not
the only satellite in the solar system. Galileo must have realized
that this is a proof for the heliocentric model of Copernicus ! (c)
The SUN : There are black spots on the sun ! (d) VENUS:
also exhibits phases like the moon (e) The MILKY WAY: The
bright patch of the sky from one end to the other had been called The
Milky Way by the Greeks. This was also known as the galaxy. Galileo
was the first to note that the Milky way consisted of an infinite
number of stars (It is now known that millions of stars like our
sun make up the Milky way. The Universe itself is made up from
millions of such galaxies) . Galieo was very quick to publish his
findings. These came out in 1610 in the form of a small book called
THE SIDEREAL MESSENGER. The book , an instant success, was sent by
The British ambassador to his monarch stating that Galileo has
overturned all the theories of ancient astronomy. The Professor of
Mathematics from Padua would no more remain anonymous! He had
became now a well known figure throughout Europe. Science itself was
about to be lifted from the depths of obscurity!
In 1611
Galieo made a triumphant entry into Rome. He was feted for his great
discoveries. Many distinguished citizens looked at the night sky and
enjoyed the new sights. However, some called it a delusion and some
others refused to look into the telescope. Galileo was buoyed up by
the honours and became bold enough to talk about his discoveries as
proof for the heliocentric model of Copernicus. Problems arose when
he started insisting that the church also receive this as the sacred
truth. He was condemned in 1614 in Florence as a heretic.
Historians believe that the opponents of Galieo were mostly scholars
and professors in the universities. He had already created enemies in
Pisa. His opposition to Aristotlean mechanics had earned him more
enemies in Padua. The money and honours he got later in Venice and
Florence had earned him the jealousy and ire of some of his
colleagues. At this time Galileo was cautioned by a well wisher that
he should be careful because of people eager to destroy him. He went
to Rome in 1916 to argue in favour of Copernican model in front of a
committee. Cardinal Robert Bellarme, the chairman of the committee,
was not just a respectable catholic but also a scholar of
mathematics. It was said that his honesty had stood in the way of his
becoming the Pope. Galileo’s arguments in favour of Copernicus were
in vain. The committee rejected Galileo’s discoveries as proofs
for the heliocentric model and also censured . The committee asked
him to refrain from giving publicity to Copernican theories. The
committee also banned publication of the book by Copernicus. This
annoyed the great astronomer Johannes Kepler who indirectly blamed
Galileo : “All this is because of people who want to interfere in
all and sundry matters”!
1621 was
a bad year for Galileo since both Robert Bellarme and Galileo’s
patron Cosmo Medici died . However he was cheered by the fact that
his benefactor Maffeo Barberini became the Pope in 1623. He was very
proud of Galileo in the first years of his rule. Galileo started a
book on astronomy in 1624. He wrote a friend at that time : I had
been to Rome to get Pope’s blessings. He had no objections at all .
It took him 6 years to complete the book. Unlike the big tomes of
those days, the book was written in Italian and not in Latin.
Galileo wanted everybody to und\erstand the book. He was probably the
first great popularizer of science . The 500 page book was not
written in the formal style, but was in the form of a series of
dialogues. The ruse could have been that author wanted to say that he
himself did not hold to beliefs in the book. The book was in the form
of a 4 act drama with 3 characters. The book which starts with due
respect to both Ptolmey and Copernicus, goes on to say “ A
scientist has done lot of research on the ideas of Nicholas
Copernicus. While these are not palatable to the church, the truths
of Nature can be found out only by science. When these truths are
understood, the glories of the Bible and God will appear more
splendid”. After he completed the book in 1630, the 66 year old
scientist went to Rome to formally submit it to the chairman of the
censor committee, father Ricardo. The committee offered several
suggestions ( some of them probably came from the Pope) which were
incorporated. The book which finally came out in 1632 was an instant
success like Galileo’s earlier works.
The title
of the book was ‘ Dialogues concerning two world systems’ and had
a picture of discussion between Aristotle , Ptolmey and Coperncius on
the front page. The geo centric theories of Greeks were compared with
the heliocentric model of Copernicus and mistakes in Aristotlean
theories were pointed out. Let us look at some of the dialogues: (1)
When the earth rotates around the sun, don’t birds get confused and
fall ? No, the movement of the earth applies to all the creatures on
earth. The earth carries the birds alongwith it (2) When you observe
some butterflies in the lower deck of a ship when it is stationary
and compare the same when the ship is moving, there wont be any
differences !( This is prelude to the Einstein’s theory which was
to come 300 years later) (3) When Simplicio, the follower of
Aristotle, asks “ Why is the universe so big? The Lord would not
have wasted so much space”, Salviati, the follower of Copernicus,
answers “ Is God’s work limited to looking after the mankind? Who
are we to limit Him? Do we have to put down anything which is not
useful to us?.” (The last sentence is a good rejoinder to people
who oppose basic research!)
The
publication of the book further angered Galileo’s opponents and
complaints to the leaders of the church started accumulating. A
scholar got annoyed that the book considered whoever opposed
Copernicus as idiots. As in the nature of authorities, another
committee was set up to look into the book in great detail. This
committee (Pope Urban chaired some meetings) stopped further sales of
the book. The Florentine ambassador wrote to his duke “ It is a
very difficult circumstance… anything could happen … His highness
(the Pope )is very angry..”. Galileo was ordered to come to Rome
from Florence. When he replied that he was not well, he was not
excused and commanded that he should come even if delayed.
There are
still many controversies about the happenings of that period. How did
Galileo get the courage to write the book? Did not he take seriously
the warning given in 1616 by the Bellarme committee or did he not
understand it properly? Or did he think too high of Pope Urban’s
fondness for him ? Maffeo Barberini had first met Galileo in 1611
and praised him to the skies : God should grant you a long life for
the good of the people ! When Galileo came to meet the new Pope in
1624, he was given immediate audience. Further there were many
discussions between them during that visit. Galileo was naturally
happy about it, Even two years later the Pope had commented very
favourably about Galieo to the duke in Florence.
But it
was also true that power did get into Pope’s head quite soon after
his ascension: I am not just another Pope ! When Galileo came to Rome
in 1930, he could meet the Pope only once. Historians give at least
3 reasons for what happened later in Galileo’s life: (1) The
church had already split once in AD 1054 ( at the time of the Chinese
guest star). Martin Luther had already split the church further in
15th century. He and his disciples were not enamoured of
science. While the Roman church itself was quite liberal, it had to
contend with the intolerant attiude of the protestants. There was the
fear that there would be again splits in the church. The 30 year war
between the protestants and catholics had already strted in 1618.
Galileo got caught in the crossfire when Pope had to show that he
could sacrifice even his close friends for the sake of ‘ truth’
(2) Galileo’s patron, Duke Ferdinand of Florence, had written to
Pope condemning his attitude to Galileo. The Florentian Duke was
friends with the Spanish cardinals who were entirely opposed to the
Pope. The punishment given to Galileo was actually a retaliation
against the Duke and Spaniards (3) The pope listened to sycophants
who said that the Pope had been ridiculed in his book. Further
Galileo had not told the Pope about the warning given to him in 1616.
It was a combination of such sentiments which was responsible for
Galileo’s problems.
Galileo’s
trial started on Feb 13th 1633 where he tried to show
that he was fair to both sides in his book .As the trial progressed
he was to say “ I have reread my book . It is as though some other
writer has written it. The tidal theory, the sun spots etc are not
proofs for Copernican model. And on the final days “ I am ready to
confess to my mistakes.. They arose out of ambitions and ignorance.
I could add discussion of one or two more days to make it even “.
But the committee was not moved. The pope who was out of town came
back and met the committee ( The basic offence for which he was
punished , according to historians, was that he ignored the warnings
of church given in 1616 and not any explicit arguments for the
heliocentric model). He was shown instruments of torture and forced
to recant. On 22nd June he was made to say “ Sun is not
at the center of the universe. It is earth “. He had to be under
house arrest throughout his life!
Galileo’s
books had always been instant successes. Further ,its banning had
added the curiosity factor. Like any banned book, its price became
much higher. But the greatness of the man was that he did not sit
ruing his fate. He was spurred on to further endeavours. He had
worked on Classical Mechanics in his youth at Pisa and Padua. He had
realized at that time itself that truth can be gotten only by
experiments. He returned to those problems and came out with a new
book : Dialogue about two new sciences. It had the same format as
that of the earlier book and the same cast of characters. He
considered it as his greatest piece of work. Einstein seems concur
with him when he says “This book shows him as the Father of Modern
Physics, nay, all Modern Science”. He sent the book to Holland in
1637 for publication. However, years of staring at the sun through
the telescope had started affecting his eye sight. At first, he lost
his right eye. Even after that he made the important discovery that
the same half of moon is seen by the earth at all times. In 1638 he
became completely blind and could not read a single line from his
newly published book. “ I increased the limits of the universe.
But today the universe is limited to me”. He died in 1642 at the
age of 80.
Galileo
wanted science to become very popular. He was also not averse to
talking about himself and his work. A combination of these two made
him a very diplomatic person in his life. He did not contradict when
the Venetians thought that he was really the inventor of the
telescope. When Venice did not honour its earlier monetary
commitments he went away to Florence. He dedicated most of his books
to the Florentian royalty. These dedications did indeed make of them
very exalted beings. He named the Jovian satellites as Medici stars(
God has willed that these new stars be named after you!). He had
good friendships with many important people in the church. They also
wanted to be seen supporting the great scientist. Galileo must have
felt very happy when Pope Paul told him not to bow down to him . But
Galileo was also very naïve regarding certain matters. He never
understood that science has no great role to play in the church
politics. He did not appreciate that church was indifferent to the
progress of science. He overestimated friendship of the likes of
Pope urban !
While
Galileo took lot of care to publicize the heliocentric model, he also
exhibited his inventions and discoveries with pomp and circumstance.
Apart from whatever personal gains this might have had, he understook
this as a way to make science popular. He showed that technological
progress is also possible through scientific studies. Galileo was
never far from want of money throughout his life. He tried to make
patents for most of his inventions. In 1597 he came out with a ‘
military compass’ ( type of a slide rule) which would simplify
calculations. Later he wrote a manual to use it and also sold it He
tried to find uses for his pendulum concept. He also tried to use his
Jovian sateliites to find the Longitude, a problem which had remained
unanswered for a long time (and remained so for a long time). While
he did get some award from Holland for this discovery, the church
forbade him to receive it.
We do not
know what would have happened if the Greek tragic playwrights had
gotten hold of his life. But what we have is the play by German
writer Brecht. Brecht who had gone against Aristotlean notions of
drama and had come out with the concept of epic theatre must have
found the life of another nemesis of Aristotle interesting. Brecht’s
Galileo criticizes himself at the end of the play: I should not have
confessed. I have cheated the whole community of scientists!. The
play was written at the time of Hiroshima and Nagasaki. Brecht
felt that if Galileo had not recanted then, there might have been a
code for scientists. May be Hiroshima would not have happened ! While
it is probably right to ask scientists who play with fire to have a
higher conscience, it is also naïve. While a scientist might have
his more than normal quota of brains, he is also a human being for
whom concepts like patriotism, duty etc are important. Brecht also
shows that the main contribution of Galileo is the scientific
temper. Galileo boasts” I gave the people inquisitiveness and
courage..Now the telescope will be trained at the establishment!”.
He gave speeches at town centers and market squares . He talked and
wrote in Italian, the language of the masses. In Brecht’s play,
Galileo’s disciple Andre mutters that a county without heroes is
damned to which his master replies that a county which waits for a
hero is damned !
Fig 1 -
Galileo
Fig 2 -
The Leaning Tower experiment
Fig 3 -
Galileo sees many more stars in the milky way
Fig 4 -
Galileo's trial
