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Hello and Welcome to Western SIV Episode
two hundred and seventy two Galleo Part four.

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Over the years spent in Padua,
Galileo had been increasingly drawn into the

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Medici sphere of influence in Florence.
That situation soared exponentially when in sixteen ten

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Galleo agreed to move to Florence to
take up the world's first ever research professorship.

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In moving to Florence, Galleo was
not only getting a better position,

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it was also moving to one of
the most important cities in Western Europe.

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And yet there were many in Galileo's
inner circle who wanted him to stay in

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Padua. Why well, The answer
is simple. The Inquisition. Italy in

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the sixteenth and early seventeenth centuries was
a patchwork of kingdoms saw under their authority

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and others subject to the authority of
foreign powers, mostly France and Spain.

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Some parts of Italy, notably Venice, were estranged from Rome. Venice was

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in fact often on the verge of
war with the Pope, but Florence was

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allied with Rome, and that meant
that the Inquisition was alive and well in

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Florence. Hence, when Galileo decided
to move to Florence. He was placing

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himself and his Copernican ideas firmly in
the crosshairs of the papacy. It was

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a decision that will come back to
haunt him. So what changed that made

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Galileo willing to such a move.
In February of sixteen oh nine, Ferdinando

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the First died and Galileo's pupil,
now Cosimo the Second, became the Grand

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Duke of Florence. Galleo immediately let
it be known that he would welcome the

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offer of a position at court,
making it clear that he was not after

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more money. No author was forthcoming, however, presumably because the Grand Duke

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was reluctant to match Galileo's vast salary, which would have made him one of

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the highest paid employees of the Florentine
government. Free time, Galileo said,

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was worth more to him than gold. With gold, one might acquire celebrity,

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but with free time he could hope
to win true fame. The previous

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summer, the Ducal Secretary had taken
Galileo under his personal protection, saying,

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as they parted, quote Galileo,
in all your activities and dealings deal with

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me and with no one else end
quote. Thus, well before Galileo discovered

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the telescope, well before he dedicated
the Starry Messenger to Cosmo, he had

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set his heart on transferring from Padua
to Florence. Galileo finally arrived in Florence

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on the twelfth of September sixteen ten. At first, much of his time

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was taken up by new observations of
the heavens, although it was not long

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before he found himself unintentionally caught up
in a bitter debate with local Aristotelian philosophers.

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The debate started in the summer of
sixteen eleven when Galileo happened to remark

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that ice floats because it's lighter than
water. The Aristotelians, faithfully following Aristotle,

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were convinced that ice is heavier than
water. Ice, they reasoned,

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is condensed water, and that it
floats because of its shape. They claimed

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flat things float because they're unable to
overcome the resistance of water, while spherical

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objects sink. Now, of course, it is so obvious to us today

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that things float because they're lighter than
water and sink because they're heavier than water,

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that it's difficult for us to imagine
a world in which the best educated

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and most sophisticated minds simply denied that
this was the case. Galileo, who

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viewed the subject as we do today, had a number of straightforward responses.

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Not only had he already worked on
specific gravity in sixteen oh eight, he

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had got caught up in an argument
with the Grand Duke's engineers, who were

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building a pontoon bridge on the Arno
as part of the arrangements for Cosimo's wedding.

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They had argued that the flat structure
of the pontoon's base would give it

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extra buoyancy, while Galileo insisted that
shape had nothing to do with whether or

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not something floated. Dal Leo argued
that an object whose specific gravity is heavier

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than water will always sink, although
sometimes it will take a very long time

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to do so. A handful of
mud may take hours to sink to the

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bottom of a large tub of water. The shape of a solid object has

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no bearing on whether it floats or
sinks. It affects only the speed with

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which it moves through the water.
Thus, a small ice cube will float.

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Now this is obvious to us,
but it wasn't in seventeenth century Florence,

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they would have seen ice only in
two forms, in thin sheets on

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the surface of ponds in the winter, and as large brocks brought down from

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the Apennine Mountains in summer to keep
their fish fresh. This disagreement involved a

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straightforward clash between the followers of Aristotle, who once again simply parroted what he

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said and held that ice is condensed
water, and Galileo, who was applying

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the principles of Archimedes, who maintained
that since ice floats, it has evidently

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expanded water. To contemporaries, Galileo's
view, which seems so straightforward to us,

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was quizzical. Matters became more interesting
when a philosopher called Ludovico de le

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Combe announced that he had an experiment
that would prove Galileo wrong. De le

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Combe was a strict Aristotelian. He
had also written about the New Star of

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sixteen oh four and suspected, surely
correctly, that Galileo had something to do

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with the mysterious Second Pamphlet from Mari, which, of course Galleo had written.

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Del Combe's experiment was simple. He
placed an ebony chip and an ebony

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ball gently onto the surface of a
bowl of water. The chip floated,

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the ball sank. Aristotle was vindicate. Dela Coombe was supposed to meet with

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Galleo to debate his experiment, but
it never turned up. Instead, he

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just kind of went around the city, demonstrating his ability to float ebonyon water

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in the public squares and crying out
that he had defeated the Great Galileo.

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In September sixteen eleven, the whole
question was discussed at the Grand Duke's dinner

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table. The discussion grew heated,
and in this atmosphere, the Grand Duke

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told Galleo to stop trying to arrange
a confrontation with Della Combe, and to

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just put his arguments in writing,
as this was the best way to ensure

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that good sense would triumph. Galileo
acknowledged the Grand Duke's advice. Galileo had

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thus learned, or believed he had
learned a valuable lesson. Debates on intellectual

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topics conducted in the court, in
the open air, or in the houses

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of leading citizens rapidly degenerated into shouting
matches. Moreover, in such circumstances,

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matic reasoning was impossible. Indeed,
when entered a sort of nightmare world in

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which the meaning of words and the
subjects discussed were constantly changing. It was

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better, he agreed now, to
write down one's arguments. That way others

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couldn't twist them and misrepresent them.
Better to abandon the court in the city

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squares and retire to one's study.
Now, Galileo was very good in debate.

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His admirers believed he could out argue
anyone. One of his most infuriating

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tricks was to offer ways of improving
his opponent's case before comprehensively demolishing it.

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But he no longer had confidence that
out arguing his opponents was enough. The

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retreat from public and court life that's
already in apparent when he wrote Discourse on

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Floating Bodies was soon to be carried
further. By January of sixteen twelve,

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Galileo was effectively living in a villa
in the countryside outside Florence. He had

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abandoned the house he had rented in
the center of Florence and had moved in

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with his friend. Eventually, what
started out as a letter to the Grand

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Duke about floating bodies turned into a
book. This was published in May of

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sixteen twelve, and it is in
this book that Galileo offered a solution to

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dela Combe's puzzle. He showed that
it wasn't because of this shape that the

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ebony chip floated. He could,
he discovered, float a needle on the

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top of the water. How could
objects float that were heavier than the water,

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well, Galileo claimed that they floated
slightly below the surface of the surrounding

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water. What was really floating was
not the ebony chip alone, because this

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would always sink if you immersed it
fully in the water, but an open

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sandwich of the ebony chip and a
layer of air, the average weight of

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the two combined being less than that
of the water they displaced. In other

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words, the ebony chip was a
bit like a boat, even though there

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were no planks holding the water back. Galileo had thus recognized that, in

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moving into his own territory that of
experimental evidence, de la Combe had indeed

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identified an interesting puzzle. He had
no idea why air would stick to the

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surface of an ebony chip, or
why water would not flow into cover the

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chip. Galileo knew only that this
is what happened. Galileo's small book provoked

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considerable comment. Four books appeared attacking
it, while Galileo's disciple Benedito Castelli published

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a substantial work defending it. Yet
it's an important book because in it Galileo

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seems to make a major transition.
He begins to concede that you can only

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discover causes through experiments, and this
new way of thinking obliged him to give

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up his belief in astrology, which
he was still defending as late as sixteen

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eleven. For all the elegance of
Galleo's arguments, which his opponents could scarcely

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ignore, the debate overfloating bodies confirmed
his growing conviction that he would never persuade

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Aristotelian professors of philosophy to agree with
his views, even if he persuaded them

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to adopt an approach that recognized the
central significance of facts. In the whole

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of his lifetime, not a single
professor of philosophy in even one university supported

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him on any topic. Mere force
of argument would never do the job.

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Now, with the benefit of hindsight, we might say that Galleo was too

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impatient an Aristotelian philosophy was to retain
a secure position in European universities for more

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than another one hundred years. In
fact, it was still being taught when

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Newton was a professor of mathematics at
Cambridge. If Galileo was going to defeat

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the Aristotelians, he needed not just
new arguments, he needed new allies.

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The publication of The Starry Messenger in
March of sixteen ten was followed by a

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carefully managed campaign to win acceptance for
Galleo's discoveries, which were so far at

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odds with everything that had went before
that they had first met with nothing but

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its skepticism. The campaign, depending
on mobilizing the resources of the Medici government

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for the honor of the Medici,
was now linked to the success of Galleo's

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publication. But most of Galleo's Venetian
friends would have been astonished if they had

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seen the first letter, or at
least surviving letter, that Galileo wrote arriving

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in Florence in September. It's addressed
to the leading Jesuit mathematician, a man

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by the name of Christopher Clavius,
whom he had visited in Rome all the

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way back in fifteen eighty seven,
and with whom he had corresponded in fifteen

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eighty eight. Clavius had written to
Galileo in sixteen oh four seeking to renew

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their friendship, but it seems evident
that Galileo had not replied. It is

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time Galileo wrote that I broke the
long silence, a silence of my pen

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rather than my thoughts with regard to
you, most reverend Sir. I break

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my silence now that I find myself
repatriated to Florence by the grace of a

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most serene grand Duke, whom it
has pleased to call me back to serve

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as his philosopher and mathematician. The
cause of my lengthy silence throughout the time

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that is that I was living in
Padua. There is no need for me

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to specify when writing to someone as
wise as yourself and quote. Both the

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Venetian political establish and the University of
Padua were hostile to the Jesuits, and

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for eighteen years Galileo had no written
communication with the Jesuits, although we know

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he had conversed on mathematical subjects with
Jesuits teaching in their Paduan college. Now

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he writes that he plans to come
at once to Rome to show Clavius and

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his colleagues the moons of Jupiter in
order to dispel any doubts that Clavius may

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have. The evidence provided by this
letter is decisive. Galleo did not move

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to Florence, thinking that the influence
there of the counter Reformation Church, though

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something of a disadvantage, was worth
putting up with in order to seize other

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opportunities. The key advantage of moving
to Florence was that it would enable him

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to travel to Rome as an intellectual
in good standing, one in the service

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of a respectable Catholic ruler, and
then to renew contact with the Jesuits.

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There are many reasons Galileo was right
to focus on the Jesuits. The Jesuit

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Order, as I'll talk more about
when we get to the Inquisition, was

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rapidly becoming the educators of Europe's elite. By the end of the sixteenth century,

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there were two hundred and forty five
Jesuit colleges. Now look today,

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the Jesuits get a bad reputation as
old sticks in the mud who refused to

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accept new ideas. That perspective,
however, ignores the very real battle going

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on within the order in the early
seventeenth century. On the one hand,

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the Jesuits prided themselves on being the
cutting edge of this new science, while

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on the other hand, the Church
remained firmly committed to upholding the traditional learning

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of the Church, primarily that of
Thomas Aquinas. Frankly, it was only

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the coming crisis within the Order itself
that Galileo played a large part in sparking

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that would see the triumph of the
traditionalist wing over the new science. Galileo

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wasn't wrong to try and ally himself
with the Order. Indeed, there were

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many within the Order who privately supported
him. However, hindsight is twenty twenty

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and we know with its value that
by sixteen thirty two the Jesuit Order would

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be one hundred percent opposed to Galileo. That being said, and I hope

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I don't have to remind you of
this. Galleo did not know that at

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the time. Galleo returned to Florence
in September of sixteen ten, about six

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months after the publication of The Starry
Messenger. At the same time, in

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Prague, Johannes Kepler, mathematician to
the Emperor, a rarity given that Kepler

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was both a Copernican, and a
Protestant received a copy of the book.

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He decided immediately to write a public
response a show of support. Kepler quickly

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realized that no one who was not
a Compernican would be able to accept the

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ramifications of Galileo's work. He wrote
that these moons of Jupiter, which he

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hadn't seen yet, were conclusive proof
that there was much more to the heavens

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than Ptolemy or Aristotle believed, And
he wrote that weeks before himself observing said

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moons again. Kepler wanted to promote
Copernicanism, and he saw through Galileo a

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great opportunity to do it. This
was great news for Galileo because other mathematicians

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were not in support of his claims. In fact, many men claimed they

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could not see these supposed moons of
Jupiter. They said Galileo had made it

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all up. Galileo was now in
a bit of a pickle. In the

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Starry Messenger, he had provided only
the most basic information about the telescope.

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He had used not enough to make
it easy for other astronomers to build replicas.

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He had, for example, withheld
probably deliberately information about the diagram,

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and greatly improved the clarity of the
image. His motive, of course,

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was straightforward. He wanted to maintain
his lead and telescope construction for as long

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as possible in the hope of making
further discoveries. And this was a sound

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strategy. But he had assumed that
there would be no difficulty in convincing people

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that the moons of Jupiter really existed. He would show them by letting them

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look through his telescope. His mistake
here was probably he didn't do it before

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publishing. As far as historians can
tell, he did not show the moons

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of Jupiter to anyone before The Starry
Messenger was published, and so Galilea was

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now committed to giving ten new telescopes
to influential rulers and cardinals. This would

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both raise the prestige of astronomy and
allow more people to see what he had

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seen. The most obvious thing for
Galileo to do here would have been to

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send the Emperor a telescope, who
could then pass it along to Kepler.

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Galileo did not do this. But
why Well, the reason is more obvious

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than you think. Galileo lived in
Florence well under the authority of the Inquisition

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he needed confirmation of his discoveries by
a Catholic scientist, not a Protestant one.

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Kepler wouldn't do him any good.
Indeed, I mean Kepler had already

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vouched for him, and it hadn't
made a difference. Galileo was thus caught

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in a double bind. He urgently
needed a respectable astronomer to confirm that Jupiter

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had moons, but there was no
astronomer here dared trust with a first rate

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telescope of his own. Manu factor. What he needed was for other astronomers

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to make their own telescopes. Kepler
tried, but his wasn't very good.

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By the end of sixteen ten,
only two people other than Galileo, as

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far as he knew, had made
telescopes of the required quality. One was

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a Jesuit in Rome, while the
other was Galileo's friend in Venice, Antonio

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Santini. Santini was surprised at how
slow others were, and Galileo probably shared

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his puzzlement. On September the fifth, Johannes Kepler confirmed the existence of the

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moons. He received a telescope from
the Elector of Colon several days prior,

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so Galileo had his confirmation, but
again it didn't help him. Reports simultaneously

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came in from Paris, and worst
of all, from Rome that other astronomers

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had tried to find the moons and
had failed. Galileo had gotten nowhere.

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On hearing in September of the failure
of Clavius's efforts to see the moon,

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Galileo immediately wrote to him, saying
that he was about to come to Rome

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and would show him the planets himself. The technique of using the telescope was

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not straightforward. He acknowledged that even
one's pulse could make it shake, rendering

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the planets invisible, and it was
too easy to mess up the lens simply

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by breathing. But instead of leaving
for Rome, Galileo grew increasingly anxious and

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depressed, and then he got sick. One can imagine his anxiety that a

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visit to Rome might turn out as
badly as another one of his visits to

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Bologne. By early November, however, Clavius, who had by now received

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two telescopes from Sanantini, had seen
four small stars moving around Jupiter. He

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was not immediately convinced that they were
planets, but he expressed no reservations.

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When he wrote to Galileo on the
seventeenth of December praising him for his wonderful

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discoveries. Santini had thus solved Galileo's
replication problem for him. He had supplied

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first rate telescopes to the two key
Catholic scientists, and had done so without

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increasing the risk Galileo was running.
Since Galileo and Santini were on very good

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terms, it seems likely that Santini
was acting as Galileo's agent. Certainly,

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he doesn't seem to have been acting
on his own behalf, as he demanded

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neither money nor fame as recompense.
Now, Galileo practically jumped out of bed

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when he read Clavius's letter. This
was the news he had been waiting for.

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Two months later, in February sixteen
eleven, Galileo wrote, there could

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be no more doubt about the existence
of the moons. When in April he

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went to Rome, the Roman College
greeted him with applause. He now had

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a small group of allies in Rome, not large, but enough to give

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him some hope. By this point, Galileo had made two new discoveries.

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First, he noticed that there seemed
to be two blurs around Saturn. He

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didn't know that these were rings,
but he knew that he saw something that

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On December the eleventh, he discovered
that Venus, like the Moon, had

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a varied appearance. It was not, in fact a perfectly round orb.

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The second discovery, the phases of
Venus, was a fundamental importance. It

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was actually discovered mostly by chance between
September twelfth and All Saints Day, which

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is the first of November. Galileo
was living in temporary rented accommodations. There.

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He couldn't mount the grinding wheels he
needed to make new lenses for his

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telescopes, and his view to the
east, where Jupiter was seen in the

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morning, was poor, so he
naturally just kind of turned his telescope to

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the west, where you could see
Venus in the evening sky. When he

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moved to the house which he intended
to make his home, which had good

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views in every direction, he continued
this program of observation. Thus Galileo had

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seen both that Venus had phases,
and, like the Moon, the planet's

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apparent size varied greatly over time.
No astronomer before sixteen ten had predicted that

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Venus would have phases because it was
first necessary to be sure that the planet

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shown only by light reflected from the
Sun. This idea was one that had

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previously been discussed as a possibility,
but the evidence seemed to be against it.

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The light coming from Venus, as
seen by the naked eye did not

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seem to vary as much as one
might expect if it had phases. Kepler,

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for example, took it for granted
that Venus shown by its own light.

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Still, Galleo came a major step
towards this prediction in The Starry Messenger

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by arguing that the light of the
Moon was entirely reflected light, and that

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the Earth too, shone by reflected
light. The implication of all this was

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earth shattering and obvious, namely that
none of the bodies that orbited the Sun

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shown by their own light. Given
this assumption, it became possible to predict

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that, if both Copernicus and Ticobrahe
were right, Venus did in fact orbit

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the Sun. In that case,
Venus would have phases, which, like

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the moons, would extend all the
way from crescent to full, while if

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Ptolomey was right, the phases would
be limited to either between full and half

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or between half crescent. The discovery
of the phases of Venus, which in

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fact, of course do extend all
the way from crescent to full could thus

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correctly be presented as evidence that Venus
must orbit the Sun and not the Earth.

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This was the first observation that was
directly incompatible with ptolemy and Ptolemaic cosmology.

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Unfortunately, for Galleo, it was
perfectly compatible with Ticobrahi's geoheliocentric system,

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and unlike with the moons of Jupiter. Both of these discoveries were confirmed by

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the Jesuits in April of sixteen eleven. Throughout all this time period, Galleo

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kept up his correspondence with Clavius in
Rome. This reflects a deliberate choice to

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rest his credibility on the Roman Church
and not on someone who was willing to

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give it, like Johannes Kepler in
the court of the Emperor. It was

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a deliberate choice whose consequences were to
become clear only many years later. I

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want to pause here and note two
things. First, Galileo was preoccupied with

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making his priority in telescopic discovery.
This is why he had rushed the starry

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Messenger through the press and why he
had announced his discoveries to Kepler. Science

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had not previously been a competition,
and we talked about this when we started

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to talk about the scientific revolution.
Certainly not in this way. Galleo had

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invented the scientist as the person who
makes discoveries. And since all you need

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in order to make these discoveries was
a good telescope, and Galileo himself was

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distributing good telescopes around the world,
he knew he only had a very small

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window in which to claim a priority. Second, I want to note a

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peculiar feature of Galleo's behavior. He
was releasing his discoveries to the words in

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sort of like drips, using Kepler
to publish his findings as if he were

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running a sort of rudimentary scientific journal. In doing so, Galileo was stepping

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away from an alternative model of scientific
activity. As soon as The Starry Messenger

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was published, he started talking of
an expanded, elegant version to be published

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in Tuscan, with accompanying dedicated poems, a book of which a prince such

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as Cosimo and a philosopher such as
Galileo could be proud. He even hoped

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to publish twenty eight engravings of the
Moon showing its changing appearance day by day

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through the lunar month. Cosmo had
advanced him the money to fund such a

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publication, and Galleo still had it
in mind in sixteen eleven. Still,

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the emphasis on a serial like publication
changed the way that science was to progress

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throughout roughly the next one hundred to
two hundred years, because the emphasis became

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on a priority becoming the first person
to discover something. You had to release

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a discovery literally the moment that you
made it. Galileo recognized this, and

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in doing his publications in this way, he set the standard for European scientists

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going forward. But there was more
in the night sky than distant planets.

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During the same period, Galileo also
noticed sun spots. Now, sun spots

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can sometimes be seen with the naked
eye. In fifteen ninety, for example,

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an English ship's captain off the coast
of West Africa saw a spot about

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the quote bigness of a shilling on
the sun end quote. Johannes Kepler saw

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a spot in sixteen oh seven when
looking at the Sun through cracks between shingles

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in the loft of his house in
order to observe a transit of mercury.

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Galleo was probably the first person to
see sunspots with a telescope. In July

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sixteen ten, after the publication of
The Starry Messenger, but before he left

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for Florence, he showed them to
a number of people in Venice. In

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the spring of sixteen eleven, he
showed them to several people in Rome,

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and a friend of his wrote to
him in the autumn of that year reporting

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what someone else had seen. In
England, a different astronomer, Thomas Harriet,

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independently observed sunspots in December of sixteen
ten. Galileo detailed his observations of

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00:30:18.720 --> 00:30:23.680
sunspots in a series of letters to
a gentleman by the name of Mark Wessler.

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Wesler was both bilingual and had studied
in Italy. He was also powerful

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00:30:29.400 --> 00:30:33.440
and wealthy, and was a member
of the ruling Catholic city of Augsburg and

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a banker to the Emperor. In
his three letters to Westler, which were

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between May and December of sixteen twelve, Galileo made three critical advances. First,

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all recent observations of sunspots had involved
looking straight at the sun through a

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00:30:48.720 --> 00:30:52.759
telescope. At dawn or dusk,
or when there was a light haze.

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One could stare at the sun for
short periods of time, particularly if using

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a color glass filter, but one
still needed ended up being temporarily blinded,

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and it was very difficult to record
what you had seen. Galleo's friend Castelli,

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00:31:08.000 --> 00:31:11.000
however, discovered that one could project
the image of the sun onto a

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00:31:11.039 --> 00:31:17.000
piece of paper held behind the telescope's
lens. The resulting image had the top

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00:31:17.039 --> 00:31:19.799
and bottom reversed, but it was
large and clear, so now you could

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00:31:19.799 --> 00:31:26.920
study sunspots without you know, going
blind. Moreover, you could record exactly

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what you had seen if you drew
a circle on the paper onto which the

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00:31:30.240 --> 00:31:33.640
image of the sun was projected.
You could adjust the distance of the paper

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from the lens until the image of
the sun exactly filled the circle. You

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00:31:38.119 --> 00:31:42.039
could then mark the sun spots on
the page simply by painting over the spots

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00:31:42.079 --> 00:31:45.839
as they appeared. The process is
a little bit trickier than it sounds,

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00:31:47.279 --> 00:31:49.599
as the sun moves pretty rapidly through
the sky, so you have to aim

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the telescope periodically. But the result
was that Galileo could now make beautifully exact

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records of his sunspot observations. Second
breakthrough evidently occurred as a result of studying

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these images, because on the twelfth
of May he wrote another correspondent to Rome

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saying that he could rigorously demonstrate his
opinion that the spots were on and not

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above the surface of the Sun.
This is again a massive argument because according

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to ptolomy, the heavenly bodies don't
change. So if the heavenly bodies don't

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change, then there shouldn't be any
change to the surface of the Sun.

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If something appeared to be different on
top of the surface of the Sun,

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well, me know, that was
perfectly explainable. But if there was some

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change to the Sun itself, well, I mean that just again shouldn't be.

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It didn't make any sense. Finally, in December, Galleo also announced

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a technical advance that was to lead
to his third breakthrough. In the Starry

356
00:32:53.720 --> 00:32:59.680
Messenger, he had provided fairly crude
images showing the relationship between Jupiter and its

357
00:32:59.680 --> 00:33:04.839
moons day by day. The images
were based on simple estimates. Galleo looked

358
00:33:04.880 --> 00:33:07.319
through his telescope and made a judgment
as to how far each moon was from

359
00:33:07.400 --> 00:33:14.279
Jupiter using his unit of distance,
Jupiter's own diameter. But in January of

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sixteen twelve he began to employ a
new method. He had attached a grid

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of lines to a plane which stuck
out from the side of his telescope,

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00:33:21.519 --> 00:33:25.359
or so we believe, because the
object doesn't survive. With a little adjustment,

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00:33:25.799 --> 00:33:30.039
he could arrange the grid so that
if he opened both eyes, when

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one was applied to the telescope,
it appeared to float over the image of

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00:33:32.720 --> 00:33:39.359
Jupiter, and its center exactly coincided
with Jupiter itself. He had constructed a

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very crude micrometer and could dismiss the
rough estimates of others as mere hallucinations.

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Now, in modern astronomic telescopes,
micrometers are mounted within the telescope itself.

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This is possible in the type of
telescope invented by Kepler, but not in

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00:33:57.559 --> 00:34:01.359
a Gallean telescope. So Galileo did
the best he could. He now simply

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00:34:01.359 --> 00:34:05.799
had to count the lines in the
grid between Jupiter and any one of its

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00:34:05.839 --> 00:34:09.000
satellites to obtain an exact measurement of
the distance, which he could then express

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in terms of diameters of Jupiter.
Galileo could now solve a problem that had

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been bothering him for the past two
years. He could accurately predict and calculate

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the periods of Jupiter's satellites, and
having done this, he could predict their

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location in the future. He put
all this together in March of sixteen thirteen.

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There Galileo supplied for the press not
only his letters on sunspots, but

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also tables predicting the positions of the
moons of Jupiter over the course of the

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00:34:40.360 --> 00:34:45.920
next few months. He thus put
the accuracy of his measurements and calculations to

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the test. While the publication was
delayed, there was still enough time left.

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00:34:51.320 --> 00:34:54.440
Once the publication was complete for people
to look at the book, look

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00:34:54.480 --> 00:35:00.840
at the moons of Jupiter, and
realize Galileo had been exactly right. Galleo,

382
00:35:00.920 --> 00:35:07.000
in the span of several years,
had taken European science and made it

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00:35:07.079 --> 00:35:14.000
more exact than it had been in
over one thousand years. He was becoming

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the world's first scientist. Now next
week we're going to start to get into

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the predictions and the arguments that are
going to set Galleo on a collision course

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00:35:28.639 --> 00:35:35.360
with the Inquisition and the Roman Catholic
Church. Now, as always, if

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00:35:35.400 --> 00:35:38.960
you'd like additional content between now and
then. You can check out the website

388
00:35:39.079 --> 00:35:44.039
link in the show notes, or
you can check out Western CIV two point

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00:35:44.119 --> 00:35:50.239
zero, available both through glow dot
com and through the Patreon feed. Both

390
00:35:50.320 --> 00:35:53.559
offer a seven day free trial,
and the links are in the show notes.

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00:35:53.920 --> 00:35:59.199
As always, appreciate Henny and all
support that you're able to give.

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00:36:00.079 --> 00:36:00.719
It keeps this crazy show going