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Hello, and welcome to Western Sieve. Episode two hundred and seventy Galileo,

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Part two. Last week I introduced
Galileo, discussed his early life, and

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more or less worked up to the
point that he was a relatively unknown professor

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the University of Padua, focusing a
lot on the differences between Aristotelian logic and

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the new type of logic that Galileo
was endeavoring to imprint on Europe. Kind

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of like fighting an uphill battle.
Unfortunately, and for frankly, hundreds of

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people in the early modern period.
That's precisely where the story ends, an

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unknown professor in some university, but
not Galileo. As we've already seen,

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there's something different in men like Copernicus, Tico, Brahe, and now Galileo.

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For thousands of years, Europe had
been ruled intellectually by classical and ancient

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philosophers, men like Plato and Aristotle, men who would have been more at

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home in the world of Socrates and
Alexander the Great than Christopher Columbus. But

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the world was changing. Galileo recognize
that that is what makes him unique,

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or, if not unique, at
least part of a new breed of European

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of a new breed of human people
today we call scientists. Certainly, if

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we think about Galileo the scientist,
the years fifteen ninety two to sixteen ten,

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when he was teaching at Padua,
were undoubtedly the most important of his

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life. During this period he made
all his major discoveries, the bulk of

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the findings that he put into his
too large as works, the Two Sciences

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and Dialogue, two of his most
consequential works, They all come from this

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period of his life. Yet our
actual record for him during these years is

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shockingly thin. That's very unfortunate for
us. The reason being is, of

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course, that during these two decades
Galileo also critically converted to Copernicism. Now,

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Copernicus published on the Revolutions of the
Heavenly Spheres in fifteen forty three,

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and he died that same year.
As we know. In his seminal work,

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Copernicus argued that the only way the
evidence of astronomy made any sense was

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if humankind accepted the proposition that the
Earth was a planet just like the others,

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and that it's like Mars and Venus
orbited around the Sun. Now,

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Copernicus's universe did have a center.
Technically, it's like really near the Sun,

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but not quite the Sun. Now, Astronomers, even astronomers of this

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age, they're perfectly happy to think
about a universe that included a moving Earth.

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After all, Copernicus pointed out time
and time again, this was the

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only way that the night sky made
any sense. But philosophers are a different

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story. And remember, in this
era, philosophers are considered much more important,

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much more prestigious than scientists. Philosophers
still desperately clinging to Aristotle, refuse

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to accept these conclusions. Again,
we must remember that science as we know

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science today was not the science of
the early modern period. First and foremost,

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philosophy and its emphasis on deductive reasoning
was the most important branch of science

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by about a million miles. Everything
else was of lesser value. Physics back

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then was merely a branch of philosophy. So long as university philosophers remained opposed

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to Copernicanism, it was dead on
arrival. Frankly, in the decades after

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his death, there were no full
fledged followers of Copernicus. Astronomers liked his

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work, but they liked it primarily
because of the accurate charts that were in

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it that simplified calculations. Nobody was
ready to die for Copernicanism or his ideas,

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at least not yet. A crucial
reason for the lack of support for

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Copernicanism lies in the existence of a
new alternative to geocentric system of Ptolome and

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the heliocentric system of Copernicus. This
was, of course, the geo heliocentric

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system of Tico Brahe first described in
print in fifteen eighty seven. According to

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Tico, the Earth was as Ptolome
and the Aristotelians claimed stationary center of the

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universe, and the sun, moon, and fixed stars revolved around the Earth.

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But the planets, Tiko argued following
Copernicus, revolved around the Sun.

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These three systems were so fundamentally different
that you might at first think it would

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be easy to find evidence to settle
the question of which one was right.

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But if one allows for adjustments of
scale, and scale is of course massive

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when we're talking about the distance between
the planets. They're each capable of making

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pretty good predictions for the positions of
the moon, the Sun, and planets

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in the sky which were identical to
those made by others. In fact,

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they're really almost geometrically equivalent. It
was soon apparent that naked eye astronomy was

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just incapable of choosing between them.
So really, then the fundamental choice is

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in which one's possible, it's which
one is plausible. Which seemed more likely

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that the Earth rotated once a day, or that all the fixed stars rotated

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around the Earth once a day,
which was more plausible, that the Earth

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was just another planet, or that
the vast bulk of the Sun circled the

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Earth every day, carrying all the
planets with it. When thinking about questions

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like these objections to a moving Earth, which were really physical honestly, rather

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than astronomical objections, all these questions
become central. Now matters started to change

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in sixteen o nine, and that's
because of new evidence, not new theories.

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And I'm talking about new evidence from
telescopic observations above all made from the

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observations of Galileo, and of course, in the same year Johannes Kepler also

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published New Astronomy, in which argued
that no theory which insisted on circular movement

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could account for the orbit of Mars, which he was claiming at least was

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an eclipse Galileo was at the forefront
of telescopic revolutions. He simply avoided discussing

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Kepler's revolutionary proposals. Frankly, he
probably doubted whether Kepler's measurements were sufficiently reliable.

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He surely found his arguments implausible,
and he probably felt that they offered

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the opponents of Copernicanism new grounds for
rejecting the Copernican system. Galileo remained,

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honestly, to the end of his
life, an old fashioned Copernican. It

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seems very likely that when Galileo became
a Copernican, he had never once in

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his life met a follower of Copernicus. There just weren't really hardly any of

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those. One of the greatest Copernicans
alive in fifteen ninety two, and certainly

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of those who had already published in
support of Copernicanism, was a man named

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Giordano Bruno. Bruno was a philosopher
rather than an astronomer. He wasn't jos

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a Copernican. He also believed that
the universe was infinite, that there were

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other inhabitants circling other sons. No. Not surprisingly, he was never able

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to secure employment as a philosopher at
any university as all of these ideas flew

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in the face of everything that had
been taught for roughly the last two thousand

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years. Bruno, we know,
was in Venice when galo Aleo arrived there

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in early September to lobby successfully for
an appointment at the University of Padua,

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an appointment that, ironically Bruno had
hoped to win for himself. But by

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September Bruno was already in prison.
He had been imprisoned by the Venetian Inquisition.

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He had been there since May,
and was be transferred to Rome in

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February of fifteen ninety three. Venice
exercised firm control over the Inquisition within Venetian

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territory. As an aside, it
seems certain that Venice would never have permitted

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Bruno to be handed over to Rome
had he been a Venetian or a teacher

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or even a student in Paduo.
But he was just a visitor, and

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the Venetian state had no interest in
protecting him. Once in Rome, Bruno

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was repeatedly tortured and eventually executed burnt
alive in the year sixteen hundred. It's

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inconceivable that Galileo did not hear about
Bruno during these early years, he worked

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in a library which contained copies of
Bruno's works. Again and again his views

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were compared to those of Bruno.
Yet in all of Galileo's surviving works,

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his books, his letters, his
notes, his drafts, there's not a

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single reference to Bruno. Curiously,
the exact charges against Bruno were and remain

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unknown to posterity. The record of
his trial was destroyed in the nineteenth century.

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We know, however, that Galileo
was influenced by Bruno for one key

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reason his rhetorical style in Plato's writings. For example, Socrates, the philosopher

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who's always right in any of Plato's
dialogues, always speaks for himself. He's

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the voice of reason, oh,
I should say, I suppose, or

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rather, Plato speaks through him,
but he's his mouthpiece. Socrates has a

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name in these dialogues for Bruno,
and subsequently Galileo. The speaker who is

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always right, man who's always in
the right, is an unnamed philosopher.

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Bruno was really the first one to
do this, and the fact that Galileo

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parroted him so clearly gives an indication
that Galileo must have known about the man.

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Now Galileo's first documented contact with a
committed Copernican came in August of fifteen

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ninety seven. He wrote a letter
to Kepler, who had published the first

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major development within Copernican astronomical theory,
a book titled The Cosmographic Mystery back in

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fifteen ninety five. This argued that
the proportions of the Solar system were determined

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by the shapes of the five regular
solids, the pyramid, the cube,

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the octahedron, the doodahedron, and
the isohedron figures with four, six,

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eight, twelve, and twenty sides
respectively. This was all first described by

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Plato. By the way, Kepler
had given two copies of a book to

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a friend who was traveling in Italy, and he ended up giving them to

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Galileo. Kepler was probably astonished to
receive a letter out of the blue in

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which Galileo, a man quite unknown
to him, declared that he had been

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a Copernican for a number of years. This letter is probably, and it

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really is, in just about every
history I've read of Galileo, the most

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important single document for understanding Galileo's intellectual
biography. It obliges us to adopt a

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very different view of Galileo's intellectual trajectory, to which could genuinely be accepted.

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Now, getting back to Galileo and
Copernicus for a moment. As a mathematician,

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Galileo would have been required to teach
different astronomical systems, and hence he

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simply must have known about Copernicus.
In Galileo's book on Motion, he references

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a technical detail described in Copernicus's work, So we know that by fifteen ninety

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two Galileo must have read Copernicus.
Again, it is unfortunate that we do

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not have any direct written evidence to
confirm these dates, but we don't,

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so we will just have to put
together what we can. What I can

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say definitively is this Galileo was not
a Copernican when he left Pisa in fifteen

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ninety two, but he became one
shortly thereafter. When Galileo wrote to Kepler

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in fifteen ninety seven, he made
a remarkable claim. He said, not

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only had he been a Copernican for
a long time, but he claimed that

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quote with this hypothesis, I have
been able to explain many natural phenomenon which,

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under the current hypothesis remained unexplainable end
quote. He had, he said,

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written at length in defense of Copernicanism, but had no intention of publishing

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while Copernicanism remained so genuinely and generally
scorned. Galileo, it's worth noting,

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was employed, like the rest of
the professors, through a series of renewable

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short term contracts, so he could
not afford to adopt in public views which

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were so genuinely disregarded. But by
fifteen ninety seven he appears to have already

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been working on an early version of
what would eventually become his masterpiece. The

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quote Dialogue concerning the two chief world
systems end quote. This is the problem.

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Though the defense of Copernicanism that Galileo
wrote sometime between fifteen ninety two and

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fifteen ninety seven has not survived.
Now there is good tangential evidence regarding Galileo's

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thinking. When he first arrived in
Venice in fifteen ninety two, his friend

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and sponsor, Guidabolo del Monte,
invited Galileo to visit him, and we

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can surely date that visit to the
summer of fifteen ninety two, and Galileo

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conducted an experiment at that time.
We have del Monte's notes, and he

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and Galileo probably did it together,
the idea for which may have indep been

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Galileo's. The experiment was very simple. Take a hard ball and code it

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with a substance that would leave a
mark. Take a hard flat surface and

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place it at an angle fairly close
to the vertical. Then throw the ball

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so that, like a pinball,
it flies across the sloping surface, first

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rising, and then after it slows
falling. What will be left behind is

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the track of the ball across the
surface, and this track should be very

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similar to the path of a ball
flying free through the air, in other

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words, the path of a projectile. The experiment showed two things. First,

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the path of the ball is symmetrical
curve. The projectile never travels in

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a straight line, and its path
while rising is identical to its path while

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falling. Second, the curve is
mathematically legible. Galileo and del Monte felt

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it was very similar to a parabola. The result, however, was a

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astonishing rejection of Aristotelian physics. According
to Aristotelian physics, an object's movement was

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governed either by nature or by force, not both simultaneously. Hence, a

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cannon ball shot out of a cannon
should proceed straight until it runs out of

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force, and then it should fall
straight down at a right angle, which

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is when nature takes over. But
of course cannon balls don't fly like that.

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Now, as an aside, by
the way, you might be sitting

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there thinking, hey, I mean
a child throwing a rock could have been

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immediately able to correct Aristotle, but
I guess that didn't happen. Galileo was

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in sixteen oh four still trying to
make sense of all this. Obviously,

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what Aristotle claimed was not how projectiles
appeared to move, So what was the

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problem? Galileo realized In the end, Aristotle could not be correct In on

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Motion. He theorized that acceleration was
temporary and that projectiles were impacted by a

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constant rate of fall, which is
true. He could never quite prove it,

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but that did remain the theory throughout
his life. When Galileo wrote on

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Motion, he was not a Copernican. He did not even address the question

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of falling bodies on a moving Earth, because even though he had formulated the

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idea of circular inertia, he assumed
that Earth was stationary. It looks very

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much, as though by the time
he left del Montes he had become a

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convert. In fact, it's even
possible that Galileo had converted del Monte,

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as he left in his papers when
he died in sixteen oh seven, a

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treatise on the Movement of the Earth. What had converted Galileo to Copernicanism was

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not some new understanding of astronomy.
It was a new approach to the problems

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of physics he had been addressing an
odd motion. Galileo became a Copernican because

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he now had the conceptual apparatus with
which to understand the physics of a moving

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Earth. But his conversion implies an
eagerness to embrace Copernicanism, for he had

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found no new evidence in favor of
it. He had merely found a way

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of refuting one of the standard objections
to it. Conversion, for Galileo was

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remarkably easy. He was a mathematician, and so could appreciate the beauties of

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the Copernican system. He was hostile
to Aristotelian philosophy, and so had no

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attachment to the Old order. Based
on some of his other writings, he

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believed neither in heaven nor in Hell, so he had no need to worry

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about where these two locations were spatially. He will have been well aware that

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the arguments that convinced him would not
have been enough to convince other more conventional

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thinkers. Though still, by the
time Galileo arrived in Venice in fifteen ninety

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two, he had formulated sophisticated responses
to the standard arguments against a moving Earth,

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arguments that went far beyond anything in
Copernicus. He could explain why objects

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dropped from a high tower appeared to
fall vertically by means of principles of circular

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inertia and combined movements, and he
could explain why objects are not thrown off

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into space by centrivigal force by comparing
the estimates of speed at which bodies fall

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towards the Earth with estimates of speed
at which they would move away from the

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Earth it projected along a tangent.
This being established, it's possible to revisit

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Galileo's remarkable claim in his letter to
Kepler that he had used Copernicanism to explain

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many natural phenomenon which were inexplicable within
conventional physics. Kepler immediately guessed that Galileo

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was talking about the tides. The
tides, believe it or not, are

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actually going to be one of sort
of this continuous problems that Galileo comes back

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to throughout his life. This seems
to have been an extraordinary leap until we

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realize that a classical source had suggested
that the tides might be linked to the

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movement of the Earth, and Kepler, by the way, was right.

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For in notes from fifteen ninety five
we find an account of the theory that

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Galileo was to put forward in sixteen
sixteen and publish in sixteen thirty two as

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proof that the Earth moves. The
basis of the argument was shockingly simple.

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If you're on a boat which a
little water has leaked into the boat,

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and the water within it travel along
quite happily. But if the boat bumps

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into a bank, the water in
the bottom of the boat carries on traveling

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forward, piling up in the front
of the boat. The tides, Galileo

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argued, must be caused by a
similar phenomenon, by some change in speed

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or the direction of the Earth's movement, which causes the water contained in the

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Earth's basins to slosh around like it
does in the bottom of a ship.

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Copernicus attribute did three movements to the
Earth, of which two were the most

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important. One was the annual movement
or on the Sun and the daily rotation

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or on the axis. The combination
of these movements would, Galileo argued,

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mean that any point on the Earth's
surface would be traveling faster, but it

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was on the side of the Earth
away from the Sun in between would experience

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acceleration or deceleration. Of course,
this is not in fact what causes the

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tides. They are caused, as
Newton will show by the gravitational attraction of

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the Moon in the Sun, but
it could cause tides in a theoretically possible

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world. The argument is valid in
principle, but not in its application to

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our particular planet. That it is
the wrong explanation for tides in our world

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was never apparent to Galileo, who
refined it to explain why tides vary at

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different times of the month and year, and we sought to explain the fundamental

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problem that there are two tides every
day rather than one. His theory would

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have implied one. Nor did Galileo
have an explanation for the fact that the

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timing of the tides varies from one
day to the next. In the new

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physics of Galileo, rest and constant
movement are indistinguishable, and this alone can

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explain how objects behave in votes.
When Galileo says he has used Copernicanism to

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explain many natural phenomena, he means
that he has used his new principle of

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the absolute relativity of movement, a
principle which must be true if Copernicanism is

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to work to explain a wide variety
of phenomena. Now, there's another discovery

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that Galileo probably had in mind when
he used the word many in his letters

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00:24:45.359 --> 00:24:49.039
to Kepler. In his first great
work, The Starry Messenger, he talks

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about a discovery quote not made recently, but rather many years ago unquote.

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This discovery related to the faint light
illuminating the dark mass of the Moon at

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New Moon. Some had claimed that
the light came from the Moon itself,

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some that it came from the stars, and some that it was the Sun's

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light shining through the translucent body of
the Moon. Galileo claimed, correctly,

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by the way, that the light
is what we now call earth shine,

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in other words, that the Earth
illuminates the Moon, just as the Moon

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illuminates the Earth. The argument he
presented wasn't new. In fact, you

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could find it in one of Leonardo
da Vinci's notebooks In The Starry Messenger.

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00:25:33.559 --> 00:25:37.920
A crucial argument for thinking of the
Earth and the Moon as alike is that

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the Moon is not, as Aristotelian
philosophers claimed it was a perfect crystalline sphere.

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Now Galleo said that was nonsense.
It has mountains, it has valleys,

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it's not a flat surface. The
mountains can be identified by the shadows

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they cast and by the fact that
their peaks are caught by the rising sun

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00:26:00.079 --> 00:26:03.839
lighting effects that are clearly visible with
a telescope. In The Starry Messenger,

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the impression is given that it is
completely new argument. But this was a

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phenomenon Galileo discovered almost as soon as
he turned his telescope to the moon in

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sixteen oh nine. Yet he showed
no initial urgency to publish this extraordinary finding.

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Then there's the next thing that he
took at issue with the Aristotelians,

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which is distance. Remember, Aristotelians
claimed that our universe was finite and frankly

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quite small. Taking the measurements of
the universe accepted by Aristotelians. Galileo maintained

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that displacing the Earth from the center
to the location of the Sun would be

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equivalent to seeing one hundred and seventy
six degrees in fifty six minutes of the

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sphere of the heavens at night and
one hundred and eighty three degrees and four

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00:26:52.200 --> 00:26:56.759
minutes during the day, a difference
equivalent if the Earth was at the center

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of the universe to seeing the heavens
from the top of a mountain one mile

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high. It's easy to see.
He argues that this difference might be imperceptible,

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and we will certainly not be aware
that the stars above our head are

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closer than the ones on the horizon
if the scale of the universe has increased,

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as the Copernican theory required. What
Galileo is trying to do here is

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put together a fundamental but critical claim. If we look at the heavens with

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the naked eye, either at a
single moment in time or over the course

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of the day, there is nothing, nothing, that we can see that

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could help us choose between the Copernican
and Toolemaic systems. Between fifteen ninety one

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and when it is Father died and
sixteen ten Galleo was engaged in a constant

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00:28:03.559 --> 00:28:08.279
struggle to try to just make ends
meet. It seems likely that his sister

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married in fifteen ninety one on terms
negotiated by his father. Galileo sadly inherited

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00:28:15.799 --> 00:28:21.079
only the obligation of paying for her
dowry, and in fifteen ninety three we

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have evidence that his brother in law
was threatening to have Galileo arrested if he

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00:28:25.079 --> 00:28:30.119
came to Florence because he hadn't paid. Galileo borrowed two hundred ducats to sort

286
00:28:30.160 --> 00:28:36.799
things out. In sixteen oh one, the marriage contract for his other sister

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00:28:36.920 --> 00:28:41.920
provided for a dowry of eighteen hundred
ducats, once again to be paid over

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00:28:41.920 --> 00:28:45.480
a period of five years by none
other than Galileo and his brother Michaelangelo,

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00:28:45.559 --> 00:28:49.400
but of course no money was going
to be coming from Michelangelo. In fact,

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00:28:51.039 --> 00:28:55.880
Galileo had just spent sixty ducats equipping
Michelangelos that he could take up a

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00:28:55.960 --> 00:29:02.000
job in Poland. In sixteen oh
two, Galleo again borrowing two hundred and

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00:29:02.039 --> 00:29:06.640
fifty ducats, which he was unable
to repay. He had to return to

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00:29:06.680 --> 00:29:11.480
his friends for help. After his
employers agreed to pay him only a year's

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00:29:11.519 --> 00:29:15.640
wages in advance, when he asked
for two. A year later, he

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00:29:15.680 --> 00:29:21.559
obtained a second year's salary in advance. Nevertheless, in March sixteen oh five,

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00:29:22.160 --> 00:29:26.240
he was once again being sued twice
for both of his sister's dowries.

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00:29:27.480 --> 00:29:33.359
Sixteen oh eight, he was forced
once again to ask for his salary in

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00:29:33.480 --> 00:29:41.440
advance. We can see how difficult
Galleo's financial position was when we recognize that

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00:29:41.480 --> 00:29:48.079
the younger sister's dowry represented close to
thirty years salary at the rate that he

300
00:29:48.160 --> 00:29:52.920
was being paid at Pisa, an
eight year salary at the rate he was

301
00:29:52.960 --> 00:29:57.680
being paid at the University of Padua. At Pisa, he had been paid

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00:29:57.759 --> 00:30:02.920
sixty ducats a year. In Padua, he who started at one hundred and

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00:30:02.960 --> 00:30:07.799
eighty florins of Venetian florin, being
worth about seventy percent of a Florentine ducat.

304
00:30:10.000 --> 00:30:12.839
Again, he got a new contract
in fifteen ninety nine and the salary

305
00:30:12.920 --> 00:30:18.799
rose to three hundred and twenty and
in sixteen oh six balloon to five hundred

306
00:30:18.839 --> 00:30:22.759
and twenty florins. His improved telescope
led to his being offered a contract for

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00:30:22.839 --> 00:30:27.279
life at one thousand florins a year, but this didn't start until sixteen twelve,

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00:30:27.559 --> 00:30:33.319
well after all of the financial problems, and in fact, in sixteen

309
00:30:33.400 --> 00:30:40.839
twelve the university stipulated that there would
be no further wage increases before sixteen oh

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00:30:40.839 --> 00:30:45.799
six. Galleo simply couldn't meet his
financial obligations out of his university salary.

311
00:30:45.720 --> 00:30:51.759
Moreover, he soon had a mistress, Maria Gamba, about whom little is

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00:30:51.799 --> 00:30:55.599
known and whom Galleo left behind when
he moved to Florence in sixteen ten,

313
00:30:56.559 --> 00:31:02.039
and children of his own to support. At three, a daughter, Virginia

314
00:31:02.160 --> 00:31:06.200
born in sixteen hundred Olivia in sixteen
oh one. By the way, as

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00:31:06.200 --> 00:31:07.759
an aside, I didn't give you
their names, but those happened to be

316
00:31:07.759 --> 00:31:11.000
the exact same names of his sisters. That's why I didn't give you the

317
00:31:11.079 --> 00:31:15.680
names, because it gets confusing.
And then he had a son, Vincenzo,

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00:31:15.720 --> 00:31:19.599
in sixteen oh six. He was
able to supplement his income by teaching,

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00:31:19.680 --> 00:31:25.519
or rather tutoring, mathematical skills required
by young gentlemen who wanted to pursue

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00:31:25.599 --> 00:31:27.880
military careers. How much he brought
in from this, though, was really

321
00:31:27.880 --> 00:31:36.319
difficult to say. Galleo probably early
on at least earned about three times more

322
00:31:36.720 --> 00:31:40.960
from private lessons people that he kept
on his borders, and the sale of

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00:31:41.000 --> 00:31:45.279
telescopes and other instruments than he did
from lecturing at the universities. So it's

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00:31:45.319 --> 00:31:52.519
fascinating to think that in these years
when Galileo was his most intellectually productive,

325
00:31:52.920 --> 00:31:56.759
he was under unbelievable financial stress and
Burton, the fact that he had the

326
00:31:56.799 --> 00:32:00.880
time to sneak away and stare at
the night Scott to develop the theories that

327
00:32:00.960 --> 00:32:07.480
he once would was just fascinating.
These were the years in which Gallea was

328
00:32:07.480 --> 00:32:13.680
carrying out an active program of experiments. Frankly, long hours of teaching probably

329
00:32:13.680 --> 00:32:17.880
seemed like an unbearable distraction. He
came to hate teaching so much that he

330
00:32:19.240 --> 00:32:23.200
later wrote about it as being equivalent
to nothing more than prostitution. It's not

331
00:32:23.240 --> 00:32:28.920
surprising that he began to long for
a better life and to make inquiries as

332
00:32:28.920 --> 00:32:32.440
to whether or not he could find
employment elsewhere. What he was looking for

333
00:32:32.559 --> 00:32:37.759
was not necessarily more money, but
more time. When he finally moved to

334
00:32:37.759 --> 00:32:42.519
Florence in sixteen ten, the salary
was about forty percent more than he was

335
00:32:42.559 --> 00:32:45.480
to have received if he remained in
Padua, but a good deal less that

336
00:32:45.720 --> 00:32:52.319
if he had stayed in Padua and
continued providing lessons. The big difference was

337
00:32:52.359 --> 00:32:55.000
that in Florence he wasn't going to
be required to do any teaching at all,

338
00:32:55.759 --> 00:33:00.240
not even the sixty and a half
hours a year were required under his

339
00:33:00.319 --> 00:33:07.039
current university contract. This was what
he called leisure time, not money or

340
00:33:07.039 --> 00:33:13.920
status. That was the irresistible attraction
that caused him to leave Padua. And

341
00:33:14.000 --> 00:33:17.720
there was another attraction though. In
Padua, Galileo had been dependent on the

342
00:33:17.759 --> 00:33:23.160
patronage of a small circle of powerful
young noblemen. They had looked after him,

343
00:33:23.559 --> 00:33:27.920
ensured his salary was regularly increased,
and arranged for it to be paid

344
00:33:27.960 --> 00:33:30.160
in advance, and of course they
had lent him money when he needed it.

345
00:33:31.119 --> 00:33:35.319
But in return they expected to be
able to make demands on his time

346
00:33:35.359 --> 00:33:38.200
and energies. They expected him,
for example, to go with them when

347
00:33:38.240 --> 00:33:43.759
they went on vacation. The demands
of such friends and patrons came to be

348
00:33:43.799 --> 00:33:50.440
seen as so burdensome that satisfying them
involved what Galileo saw as quote ceaseless labors

349
00:33:50.720 --> 00:33:55.319
end quote. It seems clear that
he had come to resent this unequal relationship.

350
00:33:57.359 --> 00:34:00.920
Luckily for Galileo, after he moved
to Florence, he had a good

351
00:34:00.960 --> 00:34:07.000
income and he was never in financial
difficulty again. When Galileo arrived in Padua,

352
00:34:07.039 --> 00:34:12.480
initially there was a major reorientation in
his intellectual interests. On Motion was

353
00:34:12.519 --> 00:34:16.639
a purely philosophical work. By contrast, his very first surviving letter from Padua

354
00:34:16.679 --> 00:34:22.159
is concerned with a practical problem in
naval technology, i e. How long

355
00:34:22.199 --> 00:34:25.519
should the ores of a galley be? There could be no more basic question

356
00:34:25.760 --> 00:34:30.679
in Mediterranean naval warfare in the period, fighting was entirely conducted, as it

357
00:34:30.760 --> 00:34:35.199
was in the Roman era, by
boats powered not by the wind, but

358
00:34:35.239 --> 00:34:39.320
by bodies of human beings. This
new interest in technology was soon reflected in

359
00:34:39.360 --> 00:34:45.320
a number of different areas of activity. Galileo wrote courses of lectures on machinery

360
00:34:45.519 --> 00:34:50.840
and on fortification. He designed and
sold his sector or compass. He designed

361
00:34:50.840 --> 00:34:54.760
a drainage pump of some kind.
His primary interest was now in applied science,

362
00:34:55.239 --> 00:34:59.840
and this new interest went hand in
hand with an interest in developing exp

363
00:35:00.119 --> 00:35:07.360
mental procedures. The birthplace of modern
science wasn't really Galleo's lecture room in Padua.

364
00:35:07.199 --> 00:35:10.559
But it was a place that the
Venetians called the Arsenal, the vast

365
00:35:10.559 --> 00:35:15.440
shipyards where vessels were built and repaired
for the Venetian Navy. But it still

366
00:35:15.480 --> 00:35:21.800
took Galleo a long time to learn
this new craft of applied sciences. Time

367
00:35:21.840 --> 00:35:27.119
and time again he got into arguments
with individuals in the Venetian Navy about how

368
00:35:27.159 --> 00:35:32.119
long the oars should be. His
fundamental problem was he never actually went down

369
00:35:32.159 --> 00:35:37.880
and talked to an oarsman. He
never talked to a shipbuilder. All of

370
00:35:37.920 --> 00:35:44.519
his models were purely theoretical, and
none of them worked in real life.

371
00:35:45.000 --> 00:35:51.880
So again, what we have here
are a lot of baby steps. Galleo

372
00:35:52.119 --> 00:36:00.719
never fully grasped that theory had its
limits and that one needed to learn from

373
00:36:00.760 --> 00:36:07.639
experience. Ultimately, what Galileo never
came to terms with was that he needed

374
00:36:07.679 --> 00:36:12.480
to use experience in order to guide
and on occasion, even change his theory.

375
00:36:13.480 --> 00:36:20.440
Galileo, though he was arguably the
world's first experimental scientist, never understood,

376
00:36:20.480 --> 00:36:27.119
at least never fully understood the need
to use experience to inform his theory.

377
00:36:27.199 --> 00:36:30.920
I don't think we should be too
critical of him for this, after

378
00:36:30.960 --> 00:36:35.679
all, Remember, we're coming out
of an intellectual age when all that mattered,

379
00:36:35.679 --> 00:36:40.119
and I mean one hundred and ten
percent was theory and deductive reason for

380
00:36:40.239 --> 00:36:44.679
one thousand years. If the theory
said one thing, but you experienced another,

381
00:36:44.719 --> 00:36:52.079
than your experience was wrong. Galileo
was slowly but surely breaking out of

382
00:36:52.079 --> 00:36:55.559
that mantra. But it would take
time. And I don't want to fault

383
00:36:55.599 --> 00:37:00.719
Galileo for his inability to jump forward
hundreds of years in just a few decades.

384
00:37:00.880 --> 00:37:07.960
Certainly, Galileo taught and studied applied
science. That being said, his

385
00:37:07.039 --> 00:37:13.599
fundamental approach to the subject was theoretical, not practical. He was interested in

386
00:37:13.760 --> 00:37:20.599
clarifying principles, not creating machines that
could actually work. In fact, of

387
00:37:20.639 --> 00:37:27.559
all the drawings and plans Galileo made, only one historians agree could have actually

388
00:37:27.880 --> 00:37:34.480
functioned. Galileo was never thinking about
real machines. He wanted a way to

389
00:37:34.559 --> 00:37:40.199
test theory. But there's no such
thing as a pulley without friction or a

390
00:37:40.320 --> 00:37:46.239
rope that has unlimited tensile strength.
Not that that stopped Galileo from writing about

391
00:37:46.280 --> 00:37:52.719
any and all of these things.
So while he might be inching towards a

392
00:37:52.800 --> 00:38:00.840
new science, his inclination was to
use his innovations to power previous thinking.

393
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All right, we're gonna leave it
there for today, before we really start

394
00:38:06.400 --> 00:38:10.239
to get into some of the heavier
astronomy in our next episode. If you're

395
00:38:10.280 --> 00:38:14.880
itching for more Western Sieve, you
can check out either of the two seven

396
00:38:14.960 --> 00:38:16.760
day free trials. In the show
notes so you can get links to the

397
00:38:16.800 --> 00:38:22.480
Patreon page into Western CIV two point
oh. Western Civ two point oh.

398
00:38:22.599 --> 00:38:25.960
We are well into the wars of
the Successors and beyond. At this point,

399
00:38:27.559 --> 00:38:30.960
Alexander the Great has been dead for
some time, and everyone's still fighting

400
00:38:31.000 --> 00:38:36.400
over the carcasses of his empire.
It's good stuff and fun, and if

401
00:38:36.400 --> 00:38:38.440
you would like to check it out, just click either link or head to

402
00:38:38.480 --> 00:39:01.440
the website links also in the show
notes. The Born