In 1564...
the year that gave England Shakespeare...
Galileo was born in Pisa...
in Italy the cradle of the Renaissance.
But Galileo was predestined for trouble.
His father was as argumentative as Galileo was to become.
The open-minded and broad education...
that the young Galileo was given in music, literature, art and science...
guaranteed that he could never hold his tongue and suffer in silence.
I think one of the significant things about Galileo in his youth...
was the influence of his father, Vincenzo Galileo.
He was very important in the musical revolution of the time...
and he helped to...
progress music from Medieval polyphony...
to more modern sort of musical structures.
Now the significance of that for Galileo himself...
was that his father held very strong views about...
the negative impact of rigid theory.
His view was that dogmatic views...
about how music should be performed...
effectively prevented music from developing.
If you look at Galileo's later career as a scientist...
you find that he's trying to present exactly the same argument...
as his father.
He held quite firmly that rigid views...
in this case the views of the Aristotelians and the scholastics...
when held dogmatically prevented the development of science...
and that was something that I think...
one could say summarized his whole career as a scientist...
the way he put himself in opposition to that kind of dogmatic view of science.
Most of his childhood is unrecorded...
but as a young boy his fascination with mechanics...
shows that his was an inquiring, unfettered mind.
It was this attitude that was to lead later...
to triumph and catastrophe.
Under the watchful eye of his father, Vincenzo...
Galileo learned to paint, play the lute and write poetry.
In the dangerous days that awaited him...
his music and painting provided a great comfort.
The boy Galileo did not go to school formally until 1574...
when the family moved to Florence.
The tremendous importance of the Renaissance was the sudden...
upsurge of interest in knowledge.
The rediscovery of the works of people such as Plato...
and in the renewed interest in the kinds of ideas...
that people like Plato were putting forward...
plus developments in music, in the arts...
and Galileo fits very well into that framework indeed.
Medical school at University in Pisa...
brought the first rumbles of discontent...
and tilts against authority that were to become his hallmark and downfall.
There his stormy temperament earned him nothing more than the nickname...
"the wrangler"...
and it was at Pisa that he first came up...
against the theories of the Greek philosopher Aristotle...
that were to dog him at every turn.
It was the fight to cut out the dead wood of Aristotle's theories...
unquestioned for centuries by State and Church alike...
that proved his undoing.
From now on the shadow of Aristotle was to blight his life.
Galileo never accepted any statement at face value.
Proof by experiment was what he demanded.
A new and exciting attitude.
Only one episode in his University career...
pointed to the way the young firebrand was to spend the rest of his life.
Galileo noticed that a chandelier swinging at the University at Petra...
always had the same length of swing, the same time swing.
That was to say that it was isotonic, the swing from one side to the other...
took the same time whether the swing was this far or this far.
It actually only applies with smaller angles...
but essentially it laid the basis for a way forming the clock...
because there was a regular period of time...
between one side and the other, no matter how long the swing might be.
The story itself may or may not be apocryphal...
but in some ways it stands for...
the kind of science that Galileo was presenting...
and therefore has enormous symbolic value...
and I think its significance lies in two areas in particular.
The first is that the observation itself is...
what scientists call counter-intuitive.
In other words it is very unexpected.
The idea that a pendulum while have the same period...
in other words it will take the same length of time to swing...
no matter how far out it is a counter-intuitive observation.
So I think that's one element of its significance...
but far more important, I think, in terms of the story of Galileo...
is that it's the story about exact mathematical measurement...
of the world as observed.
Now Galileo, as you know, was a mathematician.
He was passionately dedicated to mathematics...
but it wasn't simply an interest in mathematics...
as a subject in its own right.
He believed and he is quoted as having said publicly...
that the language of nature is written in mathematics.
So for him mathematics wasn't simply a tool...
and it wasn't simply an intellectual interest.
It was the very script by which we would understand nature...
so the story of the swinging chandelier is symbolic...
of his dedication to the idea of exact measurement...
of natural phenomena rather than simply...
sitting back and speculating about it...
as he accused the Aristotelians of doing.
He despised blind adherence to authority...
and he found medical studies full of such unthinking obedience.
As result he left University in 1585...
without a degree.
True or not, the story of the chandelier...
shows that Galileo was fascinated by measurement and the problems of physics.
As yet, Galileo was an unknown force in the world of science.
True, after leaving University...
he had immersed himself in mathematics and physics...
but he needed recognition and a University Chair...
in order to carry out research and take his studies further.
His frustration grew. Nevertheless...
he turned his powers of analysis to the problems of gravity and floatation...
and began to establish his reputation.
Then, in 1588...
he was invited to address the Academy of Florence.
This was the chance he had been praying for...
and he seized the opportunity greedily...
preparing himself, as he would later do at his trial:
with razor-sharp clarity and attention to detail.
He, Galileo, was ready to challenge the world...
and surprisingly he did so with tact...
not a quality for which he was later to be known...
combining mathematical analysis with modern and ancient literature...
to deliver a triumphant lecture. His reputation was assured.
Soon, he had the post he longed for.
In 1589 "the wrangler" now aged 25...
was appointed Professor of Mathematics at his old University, Pisa...
and he would stay true to his name.
From the new status he had acquired...
he would stoop down on narrow-minded thought...
smash the dead hand of ignorant authority.
His attacks started immediately.
The experiments at the Tower of Pisa...
possibly never happened. It has been much debated over the years.
Aristotle's theory was that bodies fell according to their weight...
so the heavier the body the faster it would fall.
Galileo disagreed with this and actually disproved it...
but he did this mathematically.
The experiment itself may never have actually taken place...
but the idea would be that you would drop two equally sized...
and equally shaped bodies in the same medium...
in this case air, and that they would drop at different rates or same rate.
If they dropped at the same rate at which Galileo is correct.
They did drop at the same rate and Galileo was correct.
Galileo's approach to science was innovative and revolutionary.
In an age of superstition he was bound to arouse suspicion...
but in using mathematics to solve the problems of physics...
and in his geometrical and numerical analysis of the way the world works...
he set the pattern for research to the present day.
Yet within this approach lay the seeds of his downfall...
for in his treaties on motion written at this time...
he shows himself open to the thought...
that the earth rotates on its own axis.
From there it was only a small step to accepting and promoting the view...
first put forward by the Polish astronomer, Nicholas Copernicus...
who had died some 45 years before.
He had declared that the Earth orbited the Sun...
and was not the center of the universe...
the heliocentric doctrine.
Aristotle's view, exactly the opposite...
was in line with teachings of the Church.
To defy it meant to face a charge of heresy...
and to risk the horrible death that this brought in its wake.
It was the challenge to this view that brought the house down around his head.
I think it's important to emphasize...
that Galileo was not arguing against Aristotle persay.
Indeed, in one of his later pamphlets he explicitly says...
that he believes that Aristotle had he been alive...
at the time of Galileo...
could have subscribed to the Galileon principles that he was expounding.
Both men were committed to the view...
that in order to understand nature one had to observe nature very carefully.
But what Galileo was arguing against wasn't Aristotle persay...
but the Aristotelians of his own day...
people who had taken Aristotle's theories...
and turned them into dogma.
People who refused accept alternative propositions.
There is, for instance, a story of...
one of his colleagues at the University, a Professor...
who refused to look through Galileo's telescope...
for fear of what he would see, because to this man...
he knew what the universe was like because Aristotle had told him that...
and he believed in it implicitly and so no further need...
to examine it more closely.
The city of Padua appeared to offer Galileo all that he could desire.
Renowned for its freedoms and independence of thought...
it seemed the ideal place for a new beginning...
and a continuation of his work.
Material success and professional reputation grew side by side...
and now began a time intense and fruitful work for Galileo:
lecturing, teaching privately and researching.
Amongst his other achievements...
he could be described as the father of modern mechanics.
Now the principle of inertia itself is...
relatively straightforward.
Put in formal language it states that it is the tendency of a body...
to remain at rest or in uniform motion...
until an external force is applied.
In other words what this means is that...
if an object is stationery it will remain stationery...
until you apply an external force, say you push it.
If it's traveling it will travel in a straight line...
until an external force is applied to alter its direction.
The same as if you role a marble down a hill...
it will keep going in a straight line until it meets a bump or a hole...
and then it will change its direction.
Now as far as we know this principle was first identified by Galileo...
and then development by Newton later on in his "first law of motion".
And still he had the energy to develop a workshop...
for producing scientific instruments...
and on top of that designing large pieces of equipment himself.
Despite this feverish activity, or perhaps because of it...
Galileo took a mistress, the lovely Marina Gamba...
with whom he lived for ten years and fathered three children...
two girls and a boy.
The youngest girl Maria Celeste was sensitive and gentle...
and during her life in a Convent...
carried out a long correspondence with her father...
one that he valued greatly and which brought him comfort...
in some of the loneliest and most frightening periods of his life.
When Galileo left Padua he also amicably left Marina.
But Galileo was not one to take the path of least resistance.
If there was no real reason to be restless he would find one...
and he now wanted to return to Florence.
Besides, he was tired of the constant round of teaching.
In 1609 an object arrived in Italy...
that was to change Galileo's situation dramatically and completely.
It flung Galileo into the wrath of the Inquisition...
and almost cost him his life, the telescope.
Excitement was at fever pitch in Italy...
although this first telescope was primitive...
no more than an innovative toy.
Once in Galileo's hand, however...
it was to alter the way mankind perceived his world...
profoundly and irrevocably.
As soon as he could...
Galileo got himself a description of the instrument...
and rushed home to build his first telescope that very night.
The first written record we have of a telescope comes from 1608...
25th September, from the Netherlands. It was the Council of Zeeland...
and they had been asked for a patent...
for what was called a spying class at the time.
A week later Hans Lipergi...
applied for a patent for his looking glass...
but it was turned down on account that these were springing up everywhere...
and it was a very simple design.
In 1609 Galileo himself for the first time, sometime in July...
saw a telescope. It magnified about three times...
but Galileo was able to actually increase this to thirty times...
by increasing the focal length and cleaning the tubes.
Again, a question not so much of inventing something...
but seeing the idea and perfecting it absolutely.
Galileo was very good with his hands.
The Dutch telescopes showed things upside down...
which wasn't so much of a problem for looking at stars.
It was a problem for looking at ships and so on and so forth.
This was because they had to convex lenses.
Galileo used a concave lens and the convex lens...
so the object itself looked the right way up.
Galileo developed the telescope...
and he developed it for a very precise reason.
He wanted to use it for scientific purposes...
and specifically to observe the heavens...
so he needed telescopes which would give him finer resolution...
and he spent a lot of time and a lot of energy...
and a lot of his own resources...
trying to develop the telescope until, as he claimed...
he developed one, which magnified the heavens by 2,000 times...
although I am not sure whether that is an exaggeration or not.
Nevertheless, because he wanted to observe the heavens...
and had discovered things about the heavens that intrigued him...
then he had an impetus to refine the telescope...
and I think it is fair to say that his efforts...
have helped the telescope to develop...
into quite a precise instrument.
The opportunity for Galileo to make his next step forward...
was not long in coming. When the Senate was considering...
whether or not to buy one of these new instruments...
Galileo immediately offered to make a better one.
To hisjoy the Senate agreed to wait and see what he could come up with.
Galileo set to work immediately...
using the best Venetian glass for the lenses.
Testing and rejecting time and time again...
struggling with the problems of distortion and magnification...
until by late August he had a telescope that he was sure...
would enhance his reputation.
It could magnify nine times.
When he presented it to the Senate success was instantaneous...
and resulted in him being awarded the Chair of Mathematics at Padua...
for life together with a salary of 1,000 Florins a year.
The popular view of Galileo...
is dropping balls off the Tower of Pisa.
I think the intellectual view of Galileo is as a giant.
A man that championed the freedom of inquiry...
and who championed exact measurement...
of natural phenomena.
This wasjust the beginning.
Galileo turned his whole workshop over to the production of telescopes...
in the attempt to make the magnification even better.
Inevitably it was only a short time before he succeeded...
and had a magnification of thirty times.
It was this telescope that he turned excitedly towards the heavens.
What Galileo saw through his telescope astounded him.
The skies opened up their secrets and wonders.
With every new discovery...
evidence for a moving Earth was presented to him...
but the sights were breathtaking to the 17th Century observer.
In his small volume called The Starry Messenger...
Galileo wrote...
"It is a most beautiful and delightful sight...
to behold the body of the Moon about 30 times larger...
and one may know with certainty that it is due to the use of our senses...
that the Moon does not possess a smooth and polished surface.
It is rough and uneven...
just like the surface of the Earth itself.
Is everywhere full of vast protuberances...
deep caverns, lofty mountains and deep valleys."
Aristotle had claimed otherwise.
The discoveries flooded in.
The Milky Way was found to be a collection of stars.
There were stars never seen before.
So numerous said Galileo was to be almost beyond belief...
and then he found that the four satellite planets of Jupiter...
were in fact in orbit around it.
Another nail was about to be hammered into the coffin of Aristotelian theory.
In Aristotle's universe there was only one sense of motion, the Earth.
Everything else either revolved around the Earth...
fell to Earth or was pushed away from the Earth.
The discovery of the moons around Jupiter meant...
to show that there were two senses of motion.
This was more in keeping with Ticonic but also Capernicum systems...
of the universe whereby the Moon would revolve around the Earth...
and the Earth would revolve around the Sun.
This was two senses of motion.
If you have 2 senses of motion there is no reason why you shouldn't have 3...
and so the discovery of the moons around Jupiter...
although they conclusively prove that the Earth went round the Sun...
almost took away the reason why one should not believe...
that there was only one sense of motion.
When Galileo first observed the moons of Jupiter he was astonished.
At first he thought he was observing fixed stars...
but when he looked again he noticed that those fixed stars moved...
and he spent some time looking at their movement...
and realized that they were rotating around Jupiter.
Now he never got around to observing and recording...
the rotations of the moons precisely...
and he suggested in one of his pamphlets The Starry Messenger...
that other astronomers should do that...
but what he did suggest was that their in Jupiter...
with it's moons orbiting around it...
was a small model of the solar system as he conceived it...
with in this case, Jupiter taking the part of the Sun...
and the moons taking the parts of the Planets...
and in particular the Earth.
Aristotle was wrong.
Galileo knew it and he was not afraid to pronounce it to the world.
He did so with the publication of The Starry Messenger.
It was a best seller and went to a second edition within months.
Galileo was famous overnight, his dream come true.
Yet successful Galileo was no more content...
than he had been as an unknown mathematician.
Not with a huge increase in salary...
or the title of Philosopher and Mathematician to the Grand Duke...
and all of Europe talking about him.
He resigned his post at Padua and returned to Florence.
Almost immediately his studies of the night sky...
led him to the discovery that Venus must be orbiting the Sun...
and not the Earth, thus adding more weight to the Copernicum theory.
As Galileo became more open and confident...
his enemies became more irate...
and determined to squash the upstart astronomer.
Unaware that a storm of unbounded ferocity was about to break over him...
Galileo went to Rome to persuaded the Catholic Order of Jesuits...
of the truth of his observations.
In this he was completely successful.
He was well received by the Pope feted wherever he went...
had his new instrument renamed as a telescope...
and returned to Florence buoyed with his good fortune.
In Florence his detractors had gathered around an arrogant academic...
named Ludovico Della Colombe and their plan was simple:
to let Galileo's defense of his own Iconoclastic view do the damage.
Galileo was a very arrogant man, he was very proud...
and this led him into trouble throughout his life.
Essentially he spent almost all of his life...
defending himself against his perceived critics...
and people who he said had taken away his ideas.
He was a dedicated scientist.
He believed in the power of exact measurement...
and that's what drove him.
He was systematic, he was careful, he was imaginative...
and I think when he was confronted by dogmatism and ignorance...
which from his view interfered with the progress of science...
I think he became very irritated and quite courageous.
Slowly they pushed Galileo towards his fate.
There were violent arguments about whether shape...
was the deciding factor in keeping an object afloat...
and Galileo fell victim to his own fiery character...
and inability to put up with fools.
He began to expostulate theories that were wildly inaccurate...
ranting about fire atoms that could pass through solid matter.
This vitriolic side to Galileo was what many hoped would prove his undoing.
They were wrong...
and it was only by corrupt, underhand means that they could finally trap him.
The rupture came with the discovery by the German Jesuit...
Father Christophe Schiner of mysterious Sun spots...
black clusters of spots on the Sun's surface.
When Galileo asserted, probably rightly...
that he had observed them first...
he tipped himself into a controversy as hot as the Sun itself.
Some, he said...
had attempted to rob me of that glory which was mine...
by pretending not to have seen my writings...
and subsequently trying to make themselves the original discoverers...
of such impressive marvels.
Schiner was enraged by the accusation.
Typically, Galileo entered the fray as only he knew how:
with all guns firing.
Ludovico Della Colombe set the trap...
and waited for Galileo to take the bait.
It was done with one question.
Is a moving Earth contrary to the Scriptures?
Now too late, Galileo saw the flaming sword...
that guarded the Church's authority turn towards him.
For a short time, turning the tables once again...
he reigned in his anger...
and with searing intelligence took the wind out of Columbe's sails...
with a brilliantly crafted letter in his defense.
The Bible, he said...
should not be used by one philosophical school...
to beat another over the head.
In December 1614...
a black cloudburst with a ferocity...
that not even Galileo's delighted enemies could have foreseen.
A Dominican, Thomaso Cacini, stood before his congregation...
and preached that mathematics was the work of the Devil...
and that mathematicians should be banned from Christian countries.
Ideas of a moving Earth, proclaimed Cacini...
were tantamount to heresy...
and the punishment for heresy was to be burned alive at the stake.
Galileo's ideas were no longer safe to hold.
Everyone knew of the Dominican, Giordano Bruno...
who had insisted on holding to the Copernicum theory of static Sun.
He had been denounced to the Inquisition...
probably tortured...
and burnt alive at the stake.
Such was the punishment for heresy.
It was not in Galileo's nature to stand idly by...
and allow the world to bejolted backwards...
by the rancorous outburst of one Priest.
Yet the Dominicans were close to the Holy Office of the Inquisition.
How could he turn the sword from his throat...
and retain his scientific integrity?
He began to feel afraid.
In 1615 Galileo was summoned to appear before the Pope in Rome.
Copernicus' book expounding the heliocentric theory...
had been suspended for correction...
a term which meant that the sections considered heretical were to be removed.
Galileo was to be brought before the Pope and warned...
that he should abandon the theory.
Aware that failure to do so meant a condemnation by the Inquisition...
Galileo determined to go through with the meeting...
accept the warning and thenceforth check his temper and wait...
for a more opportune time to push his beliefs forward.
This was not enough for Galileo's enemies...
who wanted him notjust silenced...
but out of action for good.
Adversaries in high office did what all corrupt authorities do.
Almost fatally for Galileo...
they forged the document recording the meeting with the Pope...
and placed it in the Vatican archives.
Later it was to lead him within a hair's breadth of the flames.
Galileo, the document now recorded...
had been commanded to relinquish altogether the said opinion...
that the Sun is the center of the world and immovable...
and that the Earth moves.
Nor further to hold, teach or defend it in any way whatsoever...
verbally or in writing.
As far as Galileo was concerned, however...
the poisoned cup had passed...
and he turned to scientific experiments once more.
His interest in optics led him to the invention of the microscope...
and he was preoccupied with measuring the speed acceleration...
of falling objects.
But the controversy rumbled on.
He could not keep his mouth shut when challenged...
and in his writings he was unbeatable, a master of prose...
satirical, clear and as sharp as a razor blade.
When Galileo's friend, Mateo Babilini, became Pope Urban Vlll...
the future looked full of promise...
but how deceived he was in this view Galileo was soon to find out.
In 1632 when Galileo was in his mid-sixties...
the Dialogue of the Two Great World Systems...
a 3 hundred discussion on all the points Galileo wished to champion...
was finished.
It was an attempt to bring his theory of a moving Earth back in triumph...
and it was a masterpiece.
For Galileo the existence of tides...
was the evidence he was looking for...
to demonstrate that the universe really was Copernicum...
that the Earth moved and the Sun was stationary.
As it happens his theory was completely wrong...
but nevertheless he believed that he had the evidence that he needed.
In essence Galileo's theory was that as the Earth rotated...
it created zones of acceleration and deceleration...
which effected the oceans and therefore created the tides.
Now, he argued by analogy. If you take a bowl of water, for example...
and move it backwards and forwards you get an effect...
which is entirely like tides. You get the large swells...
and the water or the liquid moving to one side then moving to another.
Now by analogy Galileo claimed...
that the movement of the Earth was creating similar forces...
to those in the bowl of water as you move it backwards and forwards...
and that this accounted for the tides.
Ironically he rejected...
what we now consider to be one of the real theories of the tides...
by rejecting the influence of the Moon...
and he did that because he was an opponent of astrology...
and to him the influence of the moon on the tides...
which had been claimed as long ago as at the time of Aristotle himself...
to Galileo it smacked of astrology and occult forces...
which he would have no truck with because...
that was not in the spirit of observational science...
for which he was standing.
Galileo had miscalculated badly...
and brought the roof about his own head.
Pope Urban was furious with this openly defiant act.
The Jesuits, releasing years of resentment...
did all that they could to stoke his anger.
The book was suspended and underwent an examination.
When he received the results he was, perhaps naively, totally dumbfounded.
The Dialogue was deemed to be unacceptable to the Church...
but worse was to follow.
Urban called in the Inquisition.
Galileo's situation had become deadly serious.
Galileo was in a state of shock when the Inquisitor at Florence...
called at his house with a formal summons.
It demanded that he present himself at Rome within thirty days...
to answer charges that were to be brought against him.
Then came the news he had feared.
Galileo was to be put on trial...
for heresy.
In Rome there followed a series of hearings and interrogations...
that were to test Galileo's beliefs and intelligence to the full.
As before, ill as he was, he argued with skill and brilliance...
to try and out-maneuver his detractors...
but this episode was to bring him to his knees.
This was no time for satirical prose. He was fighting for his life...
for his honor, for the truth.
From the archives of the Vatican came the forged document...
commanding him not to hold, teach or defend the Copernicum theory in any way.
Galileo protested that the document did not portray the facts correctly...
but it was a useless effort.
The Dialogues clearly went against the instruction.
There was no way out.
The Inquisition was not squeamish. They knew how to make people confess.
They would keep looking for a weakness...
unless he admitted guilt.
Friends begged Galileo to plead guilty...
swallow pride and vanity...
admit to having forgotten about being told to drop the theory...
of the moving Earth and stay alive.
His life rested in his own hands.
How would he decide?
There has been a lot of exaggeration about the Inquisition.
Now I personally wouldn't want to defend it as an institution...
but when the Inquisitors attempted to extract confessions from people...
I think that the evidence suggests fairly strongly...
that their favorite method was simply to tire out...
the people that they were questioning. They would keep them up...
they would deprive them of sleep, they would fire questions at them...
to breakdown their resistance. A technique, incidentally...
which is used by security forces the world over in the 20th Century.
So I don't think that the idea...
of using the horrible instruments of torture is necessarily accurate...
and I don't think that they used those kinds of methods with Galileo...
because again we have got to remember that Galileo...
was the friend of Popes and the friend of Bishops.
There was no chance of arguing his case.
Galileo had a clear choice: was truth worth dying for?
Should he endure imprisonment and torture...
and being burnt at the stake for his scientific beliefs?
Should he sacrifice himself to the principles that he knew to be right?
Did he after all possess the courage for scientific martyrdom?
With the flames dancing in his mind's eye...
and the screams of other heretics ringing in his memory...
he appeared once more before the Commissionary of the Inquisition...
and his assistants.
The proud, arrogant seeker of the truth...
was forced to confess his alleged sin.
His humiliation was complete.
"My error then has been, I confess it...
one of vainglorious ambition and pure ignorance...
and inadvertence...
and in confirmation of my assertion that I have not held...
and do not hold as true the opinion which has been condemned...
of the motion of the Earth and the stability of the Sun.
If there shall be granted to me as I desire the means and time...
to make a clear demonstration thereof...
I am ready to do so."
Having confessed Galileo now hoped for a mild sentence...
but his erstwhile friend the Pope wanted vengeance.
He wanted to destroy Galileo. His sentence was harsh.
On his knees he waited, an old and broken man...
trembling in fear beneath the long robe.
His prison sentence was confirmed, as was the banning of his book.
Then came the hardest part of all to the proud genius.
"I Galileo...
son of the late Vincenzo Galileo I...
Florentine aged 70 years have been pronounced...
by the Holy Office to be vehemently suspected of heresy...
that is to say of having held and believed...
that the Sun is the center of the world and immovable...
and that the Earth is not the center and moves.
With sincere heart and unfeigned faith I abjure...
curse and detest the aforesaid errors and heresies."
Stupidity, fear...
the greatest enemies of truth had triumphed.
The scientific movement in Italy crashed to a standstill.
The relief when he was allowed to return to Florence...
and not imprisoned after all...
was marred by another bitter blow to the old man.
His beloved daughter, Maria Celeste...
whose daily correspondence had always comforted him...
died in the spring of the following year.
Galileo was heartbroken.
It seemed he wished for nothing more than tojoin his daughter in death...
but Galileo's fighting spirit could not be crushed.
Within a short time a visitor wrote that Galileo and his friend...
a man called Picolo Ninni...
were spreading papers all over the floor with such excitement...
that one could not weary at admiration.
At the age of 69 he published Discourses and Mathematical Demonstrations...
Concerning Two New Sciences.
Far from being broken he was once again on the attack...
with Aristotle as the whipping boy.
It was another brilliant work...
touching on his favorite topic of motion and acceleration...
engineering and the philosophy of science.
One phrase, "any velocity once imparted to a moving body...
will be rigidly maintained"...
remains one of the foundation stones of physics to this day...
proving how advanced Galileo was in his thinking.
But finally, when his eyesight failed and he became blind...
he could no longer continue his experiments.
Having lived long enough for the construction...
of his satellite computer to be concluded...
with which he intended to mark the past and future position of the planets...
the bright light of his piercing, abrasive genius...
flickered and was extinguished.
Galileo, the scourge of the narrow-minded and ignorant...
died in 1642.
Galileo's main legacy was...
as part of the 16th Century and 17th Century scientific revolution...
whereby he was one of those whojoined natural philosophy to mathematics...
and take it out of the sphere of the Aristotelians working in Universities...
and just purely working off a reverence for Aristotle...
and using knowledge so the speak that was 1,000 years old...
and completely irrelevant to the modern world.
Galileo himself was an empiricist...
he could prove things by looking at the real world and this sets in...
a whole new era in science. It leads up to Newton...
and is the source of the scientific discoveries of the present day.
The importance of his work...
the principles he established in mathematics and mechanics...
that effect our lives today...
is acknowledged now some 440 years later...
by the American Space Agency, NASA...
as his space probe pushes ever wider the borders of scientific knowledge...
just as he did.
Although many people have said that Galileo...
didn't invent anything himself, and this is quite true...
and that most of his greatest work was actually just...
an expansion of other peoples work...
one couldn't possibly say that he wasn't a genius.
The man had phenomenal talent of self-publicity...
could always see the actual practical uses...
of all the abstract science that he was involved in.
However, if this wasjust a product of the Renaissance is a different matter.
It has to be said...
that at another time Galileo wouldn't have been so fortunate...
with his sponsoring by the Medici family...
and with the amount of money he got...
and that also he wouldn't have been able to make the move...
from mathematician to natural philosopher.
However, one would have to say that really...
Galileo was a genius beyond his time...
and that a lot of the things he invented and a lot of his insights...
were sixty or seventy years before his time.
I think he was a giant thinker. I think he was one of...
the giants of the intellectual Renaissance...
and I think he was a giant of modern science.
And although the forces of ignorance...
had the power to wreck a terrible vengeance...
on those who dared to stand in their path...
Galileo Galilei, an artist...
a musician, a philosopher...
a mathematician but above all a pioneer and rebel...
dared to stand and face everyone...
in pursuit of the truth.
We owe him a debt that can never be repaid.