Program 13 - "Galileo: The First Scientist"

Music"My purpose is to set forth a very new science dealingwith a very ancient subject.There is, in nature, perhaps, nothing older than motion,concerning which the books written by philosophers areneither few nor small; nevertheless I havediscovered by experiment some properties of it which are worth knowingand which have not hitherto been either observed or demonstrated.This discussion is divided into three parts.The first part deals with motion which is steady or uniform.

The second treaties of motion as we find it accelerated in nature.The third deals with the so-called violent motions and with projectiles."MusicWe're back with Science 122, the Nature of Physical Science.This is the telecourse that questions authority.Silico: "This is Program 13, Lesson 2.5, "Gal Lee Lay Oh, the First Scientist."Hey, you know, you really do have the gift of gab.The next thing, you'll want to do the whole program alone.Silico: "It might be a good idea."Hey, don't go there.Before we're done with this lesson we will have learnedabout the life of Galileo and the way in which his ideasabout the physical universe changed as he employed,for the first time, the methods of the modern scientist.We will see why and how he transformed from medieval man to modern man.How he argued against Aristotle and the Scholastic Philosophy,and we will learn about his crime against the Church.And we will see why we say that he earned the title "The Fatherof Science," or the "First Scientist," as we study hisinnovative use of the tools of science.Here are the objectives for today's lesson.These objectives are also in the Study Guide in the beginning of the lesson.

Before you begin to study the lesson, take a few minutesto read the Objectives and the Study Questions for this lesson.Look for key words and ideas as you read.Be sure to read these objectivesin the Study Guide and refer to them as you study the lesson.Focussing on the Learning Objectives will help youto study, to understand the important concepts and to synthesize.Compare the Objectives with the Study Questions for this lessonto be sure that you have the concepts under control.Hi.This is the first of our two programs on Galileo.The quote you heard at the beginning was from a bookGalileo published in 1638, called "The Discourses on Two New Sciences."Galileo and his work are important in the flowof our scientific heritage for several reasons.It's another case where it's the man as much as the ideas thatwas responsible for changes that took place.Without the passion that Galileo had to challenge the authorityand to seek the truth, things might have been very different.Of course, we'll never know, because it happened the way it happened.But Galileo's contributions have earned him the titleof "First Scientist," or sometimes even called the "Father of Science."Well schooled in classical Greek and Latin, Galileo was trainedin the priesthood and was familiarwith the Scholastic Philosophy, very familiar, in fact.

In his early years he was very much the medieval man.Against his father's wishes he studied mathematicsand he eventually earned a professorship at the University of Pisa.He wrote and delivered lectures and scholarlypapers on such Scholastic topics as the size and shape of Dante's Inferno.In other words, he's looking at the size and shape and locationof Hell, and gained a reputation all over Europefor his persuasive speaking and his intelligent scholarship.Around the age of 30, something very remarkable happened.He underwent an amazing transformation.He became, almost overnight, a modern man.During a very short period of time he became a convertto the Copernican system and he became involved in systematicstudies of motion in an attempt to prove Aristotle's views incorrect.He designed controlled experiments and he collected data on motion.He compared the data to predictions that he madeby logical discourse using his definitions of the motionsthat we saw in the last program as first principles.He engaged in Platonic dialogues in writing to argue in favorof his intuitions, just as Aristotle had done, but much morecleverly, and more correctly as it turns out.

Galileo was an intelligent, well educated, and rebellious manwho believed that people have a right to knowledge which isaccessible to their own observations.He did not like the idea of an authoritarian cosmology whichdid not correspond to observations, and he did notlike that it was the Church who dispensed knowledge in justthe right doses to keep people under political control.Galileo, in fact, was the true revolutionary.Unlike Copernicus who sort of hid things away,Galileo was out there to change things.He thought it was more appropriate to redefine thecosmology to fit the observations rather than ignore observationswhich went against the cosmology just to keep the status quo.We've already learned about his use of the telescope.But he, using the telescope to view the moons of Jupiterand seeing the faces of Venus, and the flattening of Saturn,and the mountains and craters of our own moon, marked the firstserious observational challenge to this paradigmof geocentric heavenly perfection.With the publication of a booklet, called "The Starry Messenger,"in 1610, Galileo drew attention to his Copernican viewsand set the stage for further events which would changehis life and also forever change the way we study and view our world.

In 1617, he was warned by the Church to stop teachingthe Copernican theory at the University of Padua wherehe was now a professor of mathematics.In 1632, having secured permission from the Popeto publish scholarly critiques of the twosystems, he publisheda book called, "DialoguesConcerning the Two Chief World Systems."In this book he used a Platonic dialogueto discuss the merits of the two systems.The dialogues were cleverly written in such a way thateach debate was conceded by the moderator to have been wonby the Ptolemaic advocate while it was clear to the reader thatthe Copernican viewpoint was far more logical and a far more probable system.These dialogues fooled the Church censors until Galileo'sdetractors who read much more critically thanthe censors discovered the obvious intent.Galileo was summoned by the Pope and forced to recant,and as an alternative to even worse punishment was keptconfined under house arrest until his death.While confined he completed the manuscript of "Two NewSciences," which was published in Holland in l638.In this book he detailed his studies on motion whichincluded the law of freefall, the discovery of inertia,and the explanation for projectile motion.Silico: "How did Gal Lee Lay Oh find the time to do all of these things?I barely have time to play the games you installed on my hard drive."Yeah, right, me too!That's one reason why he's the father of science and we're not.

So, let's take a closer look at this remarkabletransition from medieval to modern man.Seldom do we see an individual undergo such a change againstsuch formidable opposition, and with such an impact.So let's take a look at a resume or curriculum vitae of Galileo's life.(Crunch.)It's time for another Food for Thought.Is a cone a circle, or is a cone a triangle?So, now I want to present this little resume of Galileo.We're going to present this, intended as a guide to hischaracter and his change of character, and also the strengthof the convictions he must have had to publish this work in spiteof its disfavor in support of the Copernican theory.There are, by the way, many excellent books writtenabout Galileo, both the man and his discoveries.One of the best is simply called, "The Crime of Galileo,"and I highly recommend this to you if you like to read biographies.

So, what I'd like to do to start this out is to tryto put yourself in Galileo's place.Just try to imagine now.You are in Padua in Italy.It's late 1600s.You're 25 years old.You spent your time studying at a monastery, and well schooledin the classics, in medicine and in fact have become a scholarin the field of scholastic cosmology, travelingaround lecture, giving arguments and giving lectures about suchthings as I've mentioned before like the size and shape of hell.You've become very well known for giving very clever and persuasive arguments.In fact, people have begun to dislike you a little bit,because you're so good at being persuasive.But, now following your heart and against your parents' wishesyou decide to give up your career in the clergy and medicineand instead pursue a career in mathematics.The modern equivalent would be like dropping outof Harvard Business School to become a rock musician.Mathematicians were not very high favored in those times.So, you as Galileo now, you've heard of Kepler's theoriesand you recognize their significance in defense of heliocentrism.You're aware that Aristotle's theories of motion are suspect,and in fact, you've already largely disproven them with yourexperiments with your observations and with your logic.

Now try to imagine Galileo's reaction upon lookingthrough the telescope some 20 years later at the heavensand seeing for the first time the first real good evidencethat the heliocentric system was true and that 2500 yearsof thought, 2500 years of debate about geocentrism, is all wrong.Talk about having a peak experience.So, Galileo was born in 1564.There was almost exactly, almost exactly 20 years after the deathof Copernicus and he died in January of 1642.You might want to do some arithmetic to find out how old he was when he died.In 1556 he studied Latin at a monastery and developed notonly a good understanding of Latin, but also a pretty good command of Greek.

In 1581, he began his medical studies at the Universityof Pisa where he eventually became a lecturer.In 1587 and 88, he began delivering papers on the Siteand Dimensions of Dante's Inferno as I mentioned before.And as I mentioned before, he became quite an expert on this all over Europe.Now, you've got to try to figure that this is the ultimatemedieval man here, trying to come up with the size and dimensionsof a place that had been described by Aquinas.In 1589, he became a mathematical lecturer at the University of Pisa.This is where he studied the motion of falling bodies.And there's a legend that says that he dropped things offof the Tower of Pisa, but there's really no evidence that he did that.He did manage to anger his Aristotelian colleagueswith his brusque manner, and he also staged a little play,a little burlesque, which ridiculed the University regulationsand made the officials of the University very mad at him.

In 1592, he managed to secure a job at the University of Paduawhere the atmosphere was a little less conservative, and a littlebit less strict than it had been at Pisa.Here, in fact, he established his reputation allover Europe as a scientist and inventor.His lectures were attended by persons of the highestdistinction and he wrote numerous treatises on all kindsof different things like military architecture, and gnomonics.You know what gnomonics is?It's the study of the length of a shadow of a sun dial.The celestial sphere accelerated the motions,special problems in mechanics.He did inventions.He had machines for raising water.In fact, one of his students, his name was Torricelli hadinvented the barometer at this time to measure air pressurechanges using Galileo's theories.At this time he also did many experiments and made many observations.For example, he measured the speed of light, wrote treatiseson air pressure, measured falling objects, workedtelescopes, all kinds of different things.

In 1597, he wrote a letter to Kepler which said that he hadbecome a convert to the opinions of Copernicus many years ago,but during this time he continued to teachthe Ptolemaic system at Padua.In 1610, he wrote a book called the "Starry Messenger,""Sidereus Nuncius" was it's Latin title, in which he describedhis telescopic observations and we've already seen a reactionof Señor Sizi, the Florentine astronomer, to this particular work.In this book he recognized that the moons of Jupiter and the phasesof Venus were enough proof to disprove the Ptolemaic theory.

In 1616, he was warned not to advocate the Copernican system.You've got to understand that the Copernican system was alreadyin use by the Church during the Council of Trent,during the Catholic Reformation.The Church had adopted the Copernican calendar to make a new calendar.What happened here was that the Church was more interestedin retaining authority than it was in maintaining knowledge.The Church recognized that too much knowledge,too fast, might cause social breakdown.This is sort of what like what might happen today,for example, if we were to encounter alien intelligences.But, you know, or if we found out that the Air Force really ishiding this evidence from us, it could cause quite a bitof social unrest, and many people, today, think that there's aconspiracy of our own government to keep this stuff from us,much in the same way that the Church was keeping theknowledge of the Copernican system from the people.

In 1627, Galileo published the little book called"Il Saggiatore," in which he contends that the newastronomy is much more Copernican than it is Ptolemaic.This now, you've got to remember, is 11 yearsafter he was warned not to do this.But, he dedicated the book to Pope Urban VIII and statedin the book that a third theory is needed, since one is condemnedby the Church, the other is condemned by reason.You get it?One theory is condemned by the Church,that's the Copernican; the other by reason.In other words, he's saying that the Ptolemaic theorysimply doesn't make any sense.The publication of this book led him to an audiencewith Pope Urban, who by the way, was a former friend of Galileo'sand they sort of hung out together before Urban became Pope.

In 1632, he published book, the "Dialogues."This was a very interesting book, actually.And the two world systems, of course, the DialoguesConcerning the Chief Two World Systems.The two worlds systems are the Ptolemaic and the Copernican system.Now there's an interesting history behind this book becausehe wrote this book after his meeting with Pope Urban.And, in fact, he got the Pope's permission to publish this book.The Pope gave him permission to publisha book where he would talk about this.But the Pope warned him that the book should not favor theCopernican system, that it should favor the Ptolemaic system.So, Galileo did this.He wrote the book, but he did some things that sort of annoyed the Pope.And you know, it's one of those things, you don't want to annoy the Pope.So what he did was several things.

First of all, he wrote the thing directed at the laypublic rather than at scholars.And it wrote it in Italian, the vernacular language,rather than in scholarly Latin.Specifically so it would be accessible to those peoplewho weren't scholars, in other words, to the common people.Exactly the people whom the Church wanted to keep the information from.He also wrote the book in a very clever style.It was really a Platonic style, but he used three characters.There was Simplicio, notice the name Simplicio,who represented the Scholastic and geocentric, and medieval views.Simplicio, great name.There was Salviatti who represented the modernheliocentric view and he represented the voice of Galileohimself who was referred to in the book as simply "the Author."We'll discuss this book in a little bit more detailin the program when we get into the Dialogues.

As a moderator the character's named Sagredo,and this is where the cleverness of the writing comes in,because Sagredo conceded in each of these debates to Simplicio.In other words, Sagredo would come out after the debates wereover and say, "Well it's obvious that Simpliciois correct and the Ptolemaic theory is right."Even though it's very clear upon reading the book that Galileowas making a fool out of Simplicio, and it was actuallySalviatti whose ideas were favored.It was also interesting enough, this book wasapproved by the Church censors.The censors read it.I mean, you've got to figure, how many censors actually read the entire book?Do you suppose the Ayatollah actually read theSalman Rushdie's book before he condemned him to death?He read enough of it to decide that it was OK,because the writing style was so clever.But what happened, though, of course, was that Galileo hadmade many enemies because of his brusque style, as I said before,and many of them did actually read the book and were ableto see through what he had done, and they assertedthat he had an intent to ridicule the Church.Once this happened the Church became aware of what Galileo had done.They got really mad.At this point they started banning the book and there was a massuproar, and people started burning copies of the book.Galileo's real downfall in all this came from a letterthat he wrote to a wife of a friend.

In a conversation one night at Galileo's house this womanasked him, "Well, if you're advocating the Copernicansystem, doesn't that mean that the Bible is wrong?"And Galileo answered her in a letter saying, basically, "Yes,that technically speaking the Bible is wrong."This letter found its way back to the Pope, who, even thoughhe had been a friend of Galileo's formerly still had to do what he had to do.Which was basically to call Galileo to trial and force him to abdicate.That means to take back what he had said about Copernicus.When he was basically given the choice of renunciation or execution.And it's interesting, the parallels with Socrates here.Remember Socrates had given up his right and decided to commitsuicide rather than to be executed.

Well Galileo wasn't going to be executed.He was going to be.He said the Pope basically said, you can take back what you saidor we can turn you over to the Inquisitors.Well, Galileo was no fool.He was basically forced to sign an elaborate formalrenunciation of the Copernican theory.From then on to the rest of his life, he was held basicallyunder house arrest, a prisoner of the Inquisition, in his home near Florence.There's a wonderful story about this.And the story goes that after Galileo's renunciation he stoodup in front of the Pope and signed this document which said,"I will never teach the Copernican system, I don't believe it'strue," and as he turned away having been dismissed,he muttered under his breath, "But it moves."Speaking, of course, of the earth.Now we're talking about a man here who is very,very rebellious, and you can see this character, this strenghof character, that it takes to do this.

OK.Finally, Galileo's probably greatest work was published in 1638.This is the "Discourse on Two New Sciences."In this book he discussed materials and motion,these were the two new sciences.He talked about strength of materials and flexibilityand many of the things that we use today in modern materialscience, but he also discussed his theories on motion.He wrote this book in exile in his home in Holland.Here he discussed his earlier experiments, thingsthat he'd done 30 years before.He discussed his deductions on kinematics, things like inertiaand freefall and forces, and even hinted a little bit at the conceptof graphical analysis, which other people had done a little,but nobody had used it in the ways that we used itin the last program to apply to graphs.And, of course, I should mention here that at the same timein Holland, Rene Descartes was coming up with the analyticgeometry and its graphical analysis.So together these two things turned out to be a verypowerful mathematical technique.The book was published in Holland,and in Holland things were much looser than they were in Italy.

In Holland, in fact, the people were concerned much morewith making money than they were in retaining Church authority.And you probably remember that in this periodof time, the Dutch were very avid traders.And had established colonies in the Dutch East Indies and the United States.Henry Hudson and these guys were going around doing this.So, the fact that Holland was becoming a repositoryfor these new ideas is significant, because it allowed Galileo'swork and Descartes' work to find their way eventuallyinto England where Newton would see them later on.In this part of the lesson we'll examine the work of Galileowhich has rightfully earned him the title of "The First Scientist."We'll see how he used the right tools but used them for a jobunintended by their forgers, namely the Scholastics,following the tradition of St. Thomas.Let's put this in perspective.It had been about 300 years since Aquinas sealed the ScholasticPhilosophy with the "Summa Theologica."It's not surprising that the Scholastic philosophy had beenslowly adapted to the changing political needs of the Church,as any doctrine will alter over time as it's moldedto the desires of those who wield power.

By Galileo's time the search for new knowledge waslimited by the rigid Scholastic beliefs as wesaw in the quote previously from astronomer Sizi.The ways of the Church had become more than guidelinesfor learning, especially in the city states of Italy where theinfluence of Rome as the center of Catholicism was the strongest.To a lesser extent elsewhere in Europe, but still exertinga strong influence the authority of the Church to define and enforcespiritual and physical reality was largely unchallenged.It's in this context of social environment that we mustevaluate Galileo and his scientific work.

Now Galileo's work as a scientist is remembered for his manycontributions which included things like combining inductiveand deductive logic, his use of mathematics in new ways,his careful observations, his mathematical reasoning,the collection of analysis and data, and his controlled experiments.So that's what we want to focus on now for the remainder of this program.Because of the confrontation between Galileo and the Church,it is especially important for us to place Galileoin the social and historical context.The justification and precedent for Galileo's scholarly pursuitslay within the writings of St. Thomas himself.It was Aquinas, as you will recall, who encouraged scholarsto seek new knowledge, so as to make the Scriptures morein accord with nature, having broken Augustine's traditionof disinterest in exterior, physical reality.

Aquinas and his contemporary, Roger Bacon, had suggested theoneness of God and nature, and the importance of studying manythings, including the physical world to help understand God.These ideals had been largely buried and ignored by Galileo's time.The Church had recouped its power somewhat following thereforms initiated with the Council of Trent, which was concludedactually in the year before Galileo's birth.The Council of Trent ran from 1545 to 1563, and wasconvened by Pope Paul III to correct the abuses and defectsthat had spurred the Protestant Reformation, and at the sametime, to examine Church doctrine and to reform certain practices.In other words, the Church was really in trouble.In fact, they were at risk of losing the political hold whichthey had maintained for a thousand years.These were desperate times for the Church.The Protestant Reformation was a serious thing for the Church.The Council of Trent was actually held in three meetingsover a period of 20 years, exactly in the period between the deathof Copernicus and the birth of Galileo.

Now, this is an interesting point.There were long delays between the sessionsdue to disagreement on all kinds of things.The Germans couldn't agree with the French and the Englishand they couldn't decide where to havethe meetings and all kinds of political problems here.This is one of the ways in which, one of the first times,by the way, in which the individual politicsof the countries was beginning to interferewith the political hold of the Church.There's all kinds of things.The general disinterest of intervening Popes,and political changes going on in Germany.Some major decrees that finally were issued by the Councilinvolved clerical discipline, education and obligationsof the Church, divisions of doctrine, which were largelyconcentrated on redefining and reexamining the teachings,particularly the justification for the Church, the Mass,the sacraments, and various indulgences.These were formulated and published in the Catechismof the Council of Trent, written so explicitly,by the way, that it's still the basis to understandingthe modern Roman Catholic Church.It also points to part of a larger revival of the spiritualand theological life of the Roman Catholic Church in Europeduring the 16th and 17th centuries,sometimes referred to as the Counter-Reformation.It began as a reaction to the Protestant Reformation.Led by humanists, the scholasticism was encouragedand renewed prestige was achieved for the papacy and the Church.Bishop's duties were reformed and new monastic orders appearedincluding the Capuchins and the Jesuits.

The Council of Trent was formed in response to this weakeninginfluence of the Church, which included the formationof competing Protestant churches.Among other things, the Council incorporated the methodsof the Copernican system, using it as a mathematical device,not as a physical reality, to correct the calendar and bring itback into synch with the seasons under the influence of Pope Gregory XIII.The Gregorian calendar is basically the one we use today.And it was found to be out of synch.I think we mentioned that in the program on Copernicus.The Reformation of the Church also had another effect.It ushered in the baroque period of art, architecture and music.This was largely an attempt by the Church to get peopleto attend Masses, so basically the Church added theater to its services.The churches were redesigned with lavishartwork and stained glass windows.Music was added to the liturgy in an attempt to increase theinterest in Church attendance, and also to draw members awayfrom the competing Protestant churches.The political power of the Church was nowhere stronger than itwas in the states of Italy where Galileo was born,exactly one year after the Council of Trent ended.This is interesting.

Another case of the right man at the right time,because if Galileo had been born one generation earlier,if he would have been a young man whose rebelliousness could havecontributed to the reform of the Church, it might havebeen a very different story.But as it was, Galileo emerged into adulthood justat the instant when the Church was reestablishing its powerby authority following the Reformation, and they were notabout to tolerate anybody messing with it.At least no one as arrogant and bullheaded as Galileo was.Galileo was described as being bullheaded and arrogant, and he was.He was self confident and rebellious.Unlike Copernicus, whose name the revolution bears,Galileo was really the revolutionary.Now in many ways this is similar to the discovery of America.What I mean by that is that it was Columbus who discoveredor "found" the New World, but he thought he was somewhere else.The country was named after Amerigo Vespuci.Just think of that, we might have been known as Vespucia instead of America.Anyway, Vespuci knew where he was, whereas, Columbus was lost.And in similar fashion, Copernicus found a heliocentric solarsystem but he didn't know what he had, claiming it to be nothingmore than a Ptolemaic device to facilitatecalculations of the planetrary orbits.

Galileo realized that the world of Copernicus was consistentwith his observations with the telescope, but also with hislogical arguments and with his experiments.By the way, about which he would not publish until 30 years laterafter he had already gone through all this stuff with the Church.You will recall that in the Scholastic philosophyof Aquinas, seeking new knowledge was actuallyencouraged, unlike Augustine's warning to seek only internal knowledge.The Scholastics not only sought new spiritual knowledgethrough the Scriptures, but also from the ancient philosophers.They applied the methods of inquiry of the ancientsto study all aspect of the physical and spiritual world, with littledistinction between the two worlds.Following the ideas of Roger Bacon, Aquinas himself hadstated that nature and God could not be separated.He conjectured that since everything in nature comesfrom God, then studying nature is a way of studying God.

In the spirit of a paradigm, the types of questions which wereappropriate for study were determined by the paradigm.The two statements that we'll see on the screen,both from Aquinas' Summa Theologica, will serve to illustrate this."From the Divine World, the Sacred Scripture and Naturedid both alike proceed...nor does God less admirably discoverhimself to us in Nature's actions thanin the Scriptures' sacred dictions.Revelation cannot conflict with reason.While separate, they rest on the one absolute truth."Although Galileo was schooled in the classics and the Scholasticmethods, and used them to guide his questioning, accordingto his contemporaries, he simply asked the wrong kinds of questions.

The change in the style of questioning was thebeginning of the modern era in science.It is a classic example of a paradigm shift, where suddenlysomeone sees the world in a different way.Once the system was understood, this is the system of askingquestions, was understood in a different way, then it waspossible to ask different kinds of questions as well as different questions.There's a difference here.Different kinds of questions as well as different questions.Of the two, the kind of question is probably moreimportant than the questions themselves.For one thing, Galileo began to ask questions for which a definitiveanswer could be found, not just a speculative one.These specific questions, such as, how far a ball will roll in acertain amount of time, on the slope of a particular angle,were viewed as meaningless and too generalby his Scholastic contemporaries.Interesting isn't it that his specific questions were considered too general.How can that be?While we consider their specific questions too vague.Like night and day, these two things are vastly different,and not just in terms of simple things like geocentrism and circles.There's a whole different world involved here.Galileo's contemporaries, in fact, thought his approach was"fantastic, his conclusions preposterous, haughty and often impious."You might say it's like seeing the face whileeveryone else sees the vase, if you know what I mean.We're about to encounter our first example of what we like to callthe Certs or Miller Lite type of controversy.The name of this type comes from two TV ads.

Now some of you may be old enough to remember one or the other of these ads.In one case the question is whether Certs is a candy mint or a breath mint.You remember the ad."Certs is a candy mint, Certs is a breath mint."And the other one we see arguments about whetherMiller Lite tastes great, less filling."And people chant back and forth.So we see arguments amongst friends and people taking sidesand chanting and other typically human behaviors in regard to these questions.The eventual message in the ads is that Certs is botha candy mint and a breath mint.And Miller Lite is both great tasting and less filling.The allegory is clear here.

In the history of science, as in other endeavors, these typesof Certs/Miller Lite controversies take place all the time.Is personality nature or nurture?Is light a wave or is it a particle?Does heat flow like fluid or is it a form of energy?Is economics driven by supply or demand?In most cases, the approach that's been first takenwas to argue about which thing it is.Is light a wave, is light a particle?Is it nurture, is it nature?Eventually great strides are made when the realization comes thatit is both, unimaginable as it may be.Then the question becomes how can it be both?What properties can this thing have that will allowit to display features of both?It kind of reminds you of the face in the vase or the young lady and the hag.You remember from Lesson 3?We've seen how the use of formalized logic has beenused since the time of the ancient Greeks.We have even briefly discussed some aspects of that logic,and we've seen it in operation on several occasions.We have mentioned inductive and deductive logic on several occasions.

Now it's time for us to take a closer look at the two forms.Although they're not the only forms of logic, they'reimportant, among other reasons, because it was Galileo's useof deduction and induction as complementary and reinforcingmethods which characterized the transition into the scientific age.We'll see that it will be Newton who's really the master of thismethod, but really he learned it from Galileo.The first type we want to look at is induction.Induction is the process of discovering underlyinglaws, rules and principles from observation.This would be like writing a rule book after watching the game.So, you go to a baseball game and after it's done you write down the rules.It's the process used in understanding the rulesof grammar or a spoken or written language,or in something likedeciphering a hieroglyphic.

Francis Bacon was an advocate of the inductive method.He argued that knowledge can be attained and organized mosteffectively using induction to ascertain the rulesby which the universe operates.This is also what Aristotle did in formulating his explanationsfor motions and change in the universe.One of the most famous inductions in the history of science is Kepler's laws.Can you explain why these are inductive laws?See, like Aristotle, Bacon failed to characterizeknowledge and learning by induction alone.On the other hand, deduction is the process of predicting outcomesbased upon the knowledge of first principles, such as laws or rules.This would be like predicting that the orbit of a planet by knowingthe principles that govern its motion.It's the process used when making astronomical charts based on Newton's laws.This is similar to what Plato did with whatwe call Plato's question in Lesson 6.Starting with the first principles of circular perfectionand mathematics, how is the universe structured?It was Rene Descartes who was a strong proponent of the deductive method.He believed, like Plato, that observations are not trustworthy.

Descartes sought to start from first principlesand argue logically to derive results.One of the things that Descartes argued for was that thespiritual and physical universes were of a different natureand could be only properly understood by applyingdifferent methods to the two.For example, the separation of the mind and body still allows usto study nature as something separate from ourselves.It also allows us to come to justify the rape of the planetand its resources as we arrogantly assume that the planet,and perhaps the entire universe is made for our use.It's also very Christian, that is the ideaof the separation of the soul from the physical body.Descartes' famous statement, "I think, therefore I am,"in Latin "Cogito ergo est," might be viewed as the confirmationof the existence of the individual as somethingwhich must be explained and rationalized.

Now come to think of it, it's amazing that we existand can contemplate the universe which created us,whatever it's cause and whatever its reason.It's a good first principle.I might paraphrase Descartes to say, "I exist, now what!"What do you think it means?It was the combination of the two methods which lead to greatsuccess, first for Galileo, and later for Newton and science in general.The interaction of induction and deduction reinforce one another,like the graphite and resin in a high tech composite material.When combined with experimental observation and measurements,the three form a triangle of strength.Not coincidentally the same sort of strength is the foundationof our democracy, with the legislative, judicialand executive branches exerting checks and balances on one another.We shall see that Thomas Jefferson was a great fanof Isaac Newton, oh, but we're getting ahead of the story again.Study this diagram in the Study Guide.You may want to make a note of this figure and refer to itin a later lessons as we watch the scientificmethod unfold the mysteries of the physical world.

Now we're ready to specify the tools that Galileo used in his work.We do this as a way of introducing the studentto the structure of the "scientific method."We've deliberately chosen to present this material in a nonlinear way.We do this so that you, the student, is not misleadinto memorizing formulas and facts.That would be like running headon into a tree whileyou're searching for the forest.So we don't want to do that.We will list and delineate these tools now, and in the nextlesson we'll be specific when we look at the developmentof Galileo's ideas in the context of these fourtools or methods, whatever you want to call them.We're interested in the way in which all of these things thatGalileo did affected him, and specifically how they allowedhim to be convinced of the truth of the Copernican systemwith such fervor that he was willing to risk the wrathof the Inquisitions to publish them.

We'll see in later lessons that modern science really is theimplementation of these tools to various degrees,and sometimes with more success than others.After all, having the right tools doesn't necessarilymean that you can fix your car.Galileo used both inductive and deductive logicin the interactive sense we describe in the focus earlier in this lesson.When we study his methods and ideas in the next lesson, look for this interaction.Similarly, when we study Newton's developmentof the law of gravity, we will see a true master of the technique.In his writings, Galileo employed the age oldPlatonic dialogue, but with a new twist.Instead of two characters engaging in dialogue, Galileo used three.He had one character arguing each opposing point of viewand a third character, a moderator, to keep the discussion focused.In here we see this triangle of interactionin a different sense than we examined in the focus.Galileo made many different types of observations, but theyseemed to fall into three different types.These included observing objects in freefall, data collectedthrough controlled experiments and observations through thetelescope which he also significantly improved over a period of ten years.

Galileo's alleged to have staged this public demonstrationdropping lead balls of different sizes and weight off the towerof Pisa, to prove that they all fall at the same speed, contrary to Aristotle.It's a nice story, but there's really no evidence thatGalileo did it, probably someone else did it.There is no documentation to support this at all.But Galileo was not the only one dropping things, nor was he theonly one questioning this aspect of Aristotle's natural motion.Well, at least Galileo didn't do this at Pisa.He's known to have staged such shows for visitors at his homeas an after dinner act, usually followed by a persuasive speechabout the errors of Aristotle's theories on motion.But most of his guests simply shrugged it off as a parlor trickand were neither convinced nor converted.

Galileo did extensive experiments over a period of many years.But most notable were his experiments with the inclinedplane, rolling balls of different sizes, different materials,and different surfaces while he collected data on the distance and time.It's these experiments that we will undertake to understand in our next program.It is not just the experiments that interest us.It's also the design of the experiments, the way Galileocollected and analyzed data, the conclusions that he drew,the inferences that he made, and even the accidental discoverieswhich might have escaped in a less adept experimenter.You will notice that we include experiments here as a typeof observation, but also as a separate category.That's because the experiment is a special kind of controlledobservation, usually in the form of a controlled experiment,some simplified model of a more complex system.We've already noted Galileo's observations through the telescope in Lesson 10.And here we'll concern ourselves with the significance of thesediscoveries so far as they support the new world view.

Well, one of the first things Galileo noticed was sunspots,and this simply indicated to him that the world, the universe was not perfect.After all the sun has zits then the heavenly objects can't be that perfect.The same goes for craters on the moon.The moon turned out to be an earth like object not a heavenlyobject, having features very similar to the earth.And, of course, the phases of Venus we've already discussed.In the Ptolemaic system it's impossible for Venus to show a full set of phases.The moons of Jupiter were observed by Galileo through the telescope.We've already seen Señor Sizi's response to this, and, of course,this indicates that if there's a second center of motionin the universe, then the sun can't be, the earth can't be the main center.So, if Jupiter can have moons going around it, then why can'tthe earth not be the center of motion as well?Galileo also observed that the planet Saturn was not a perfectcircle, that, in fact, it was flattened, it's actually ovalshaped, and this, we know today, is due to extreme rotation ratewhich tends to sort of splay it out at the Equator.And the last thing here is the pinpoint stars of the Milky Way.

Galileo noticed through the telescope that there were manymore stars available through the telescope than therewere through the naked eye.And this, of course, means that there are many things there that can't be seen.In other words, that the heavens are not perfect.That there are new stars available in the sky.The idea of the experiment wasn't new with Galileo.Francis Bacon who espoused an inductive approach was alsoa contemporary of Galileo, and the idea of testing reality had beenpublished by Roger Bacon back in the time of St. Thomas Aquinas.Galileo stands out as the experimenterbecause his experiments were well designed.They used well defined and easily measurable variables orparameters and they allowed him to control the experimentby holding all but one of the variables constant while changing the others.So he could see the effect of changing one of the things.

The process of collecting and analyzing data is oftenoverlooked as an important contribution of Galileo to the scientific method.Although we know this is done, most of us don't do it most of the time.It's not as easy as it looks to keep a record of the variablesand the conditions which lends themselvesto the interpretation at some later time.You will no doubt experience some of these difficultiesin your own efforts in the lab exercise.Before Galileo, mathematics was only for doing calculations,things like predicting planetary motions and keeping trackof inventories and shipments and other practical things like that.Kepler had introduced some general laws using Brahe's datain relationships in mathematics, but it wasstill basically for doing calculations.It was Galileo who really began to use mathematics for defining,deriving and understanding relationships.The key word here is relationships.For whatever reason Pythagorean or otherwise,these relationships do exist.

Galileo was one of the first to recognize that it is notnecessary to understand why the relationships exist in orderto know what the relationships are.Concentrating on the relationships instead of on their meaningswas one of the ways in which Galileo departed from thescholasticism of his contemporaries and for whichthey found his methods to be unorthodox.In Lesson 12 we saw how analytic geometry can be usedin the graphical analysis of motion, and how the graphsgenerated by these relationships are related to the geometric shapes.But the shapes and the properties of the graphs are not relatedto the numbers so much as they are relatedto the relationships between the numbers.For example, the fact that direct proportions existin nature is a powerful prediction tool.Once we can show that such a linear relationship exists.If we can't show the linear relationship exists,then we can't use the analytic geometry asa tool to see what the relationships are.

So in the laboratory exercises you'll have an opportunityto explore these linear relationships of various types.Before we give too much credit to Galileofor his mathematics, we must return to Descartes.In Holland, around the same time that Galileo was writing hisfinal work, Rene Descartes, exiled from his homeland in Francefor his radical ideas, was dreaming up the mathematicsthat we now call analytic geometry.Combined with his reliance on deductive logic, as we notedearlier, and a preference for studying the spiritual worldseparately from the physical world, Descartes provided theperfect complement to Galileo's studies, and set the stagefor Newton in the next generation of our scientific heritage.In Program 12 we combined Galileo's algebra with Cartesiananalytic geometry to see motion from a modern perspective.

We want to remember that Galileo did all this without benefitof the powerful visualization tool of graphics.He also did it without our modern algebraic notation.This serves as another tribute to this great intellect.In Galileo's writings we see hints of Cartesian analytic geometryas well as a forbearance of Newton's laws in the next generation.Imagine what Galileo with his mathematical skillsand his resolve might have done if he had all these tools!So, Galileo's use of mathematics generally falls into three types.Analytic Geometry is the name given to a branchof mathematics which deals with the nature of equations,the types of relationships, and shapes and properties of the graphs generated.The coordinate system we use to draw these graphs is a cleverway of showing the relationships in a pictorial form.From the geometric properties of the figures which are generatedwe can learn information about the relationships themselves.This is an important contribution, and one that Galileo himself didnot formalize the way that Descartes did.It's not entirely clear how one would know whethera certain behavior has taken place, even after themeasurements have been made.For example, if you were doing a study of whether or notviolence, watching television causes violence in children,you would have to define very clearly what youwere going to call a violent behavior.It's no different in the physical sciences.Without some way of analyzing the data, and deciding whetheror not the predicted behavior has taken place, the experimentand the data collected is entirely useless.

Now this is especially true in Galileo's case where he wastrying to determine whether or not objects underwent uniformacceleration, without being able to measure acceleration directly.He had to make measurements of distance and time and somehowuse these relationships to determine acceleration.Verifying these relationships is much easier for us todaybecause we've developed many techniques of graphical analysisand statistical regression, and all kinds of things like that.In Galileo's time none of these techniques existed yet.As we'll discover in our own laboratory exercises, becauseof errors in measuring, it's not always possible to distinguishclearly what kind of relationship exists between two parameters.Using algebraic logic, Galileo derived a relationshipbetween distance and time which would allow him to determinewhether gravitational acceleration was uniformand whether it was the same for all objects.We saw this relationship briefly in Lesson 12, but we'll repeat it here.You'll see this again in Lesson 14.The mathematical wizardry that we see on the screen herepredicts that in uniformly accelerated motion there shouldbe a direct proportion between distance and the second power of time.Don't panic if this doesn't register just yet.Let it bounce around in your mind, and we'll come back to it several times.

So what I want to do now is go to the ELMO and sortof derive this relationship for you. So, let's go to the ELMO and derive this relationship a little more closely.What we're working with here is Galileo's equations.You may remember that Galileo defined distanceas the average velocity times time.Well, actually he defined it first as velocity isdistance divided by time, but this is the same thing.He also then defined the velocity as acceleration times time.Now, this only holds true when the initial velocity is zero.In other words, when you're starting from rest.We have to put that condition in because itadds something to the equations, if we don't include it.So, here's the way this works.We learned from our graph the last time that the average velocity,and uniform acceleration is equal to one half of the final velocity.So, now here's what we can do.We note here that distance is average velocity multiplied by time.So, let's take this expression for average velocity and put it inplace of the average velocity here.So, I'll write this, this way.Distance is equal to one half times the velocity times the time.I simply substituted one half "D" in place of the "D" bar for average velocity.OK.

Now we understand that velocity, that's this term,is equally to acceleration times time.So, let me put "A" times "T" in the expression here for velocity.So, distance now is equal to one half times acceleration timestime and then multiply it once again by time.So, what we see here is that the expression time appears twice in the equation.Once here and once from the term for acceleration.What this amounts to is when you do the algebra and combine theterms, that the distance traveled is equal to one half timesthe acceleration times the square of the time.In other words, what we see here is that although you cannotmeasure acceleration directly, you can determine whether or notacceleration is uniform because there's arelationship between distance and the square of time.This symbol that looks like the Greek letter Alphasimply means it's proportional to.So, what we see here is that we can determine whether or notsomething is uniformly accelerated simplyby measuring the distance that it travels and comparing thatto the second power of the time, not the first powerof the time, but the second power.This is a very powerful sort of relationship because it allowsus to measure things like distance and time and to determine aquestion about uniform acceleration which cannotin any way be determined otherwise.So, this appearance of time twice in the relationship and theproportionality between distance and the square of time issomething unheard of, even in Galileo's time.

It was Galileo who originated this idea.Let's go back to the ELMO and explore this relationship a little bit more closely.What we're dealing with here is this relationshipbetween distance and the square of time.Let's see what this means.One way we can explain this or we can look at this is to say thatthis means that something will travel four times the distancein twice the amount of time if it's uniformly accelerated.So, let's look at a little diagram here.Suppose that you have an inclined plane.Or suppose you have a tilted surface, and you're rolling a ball down the surface.So rolling a ball down the surface in a certain amount of time,it will cover a certain amount of distance.OK.So, here's certain amount of distance and a certain amount of time.Suppose just to keep track of things, I call this "D-1"and "T-1."So, this is the distance,"D-1."It will travel in the time"T-1."So, let's suppose we measure that distance,"D-1" and "T-1"and keep track of them over here in a table.Here's distance and here's time.So, let's suppose that in this particular interval of time,let's say it's in one second, that we observe that the ball rolls 10 centimeters.

So, now, we let the ball next time roll until it has rolled 4 times as much.So, we let the ball roll now, starting from rest, until it hasrolled a distance, that's called "D-2," which will be all the wayfrom the top and it does that in a time, "T-2."How would the distance and the time compare with each other?Well, this relationship between distance and the square of timemeans that if we take 4 times the distance and make this 40centimeters, we would expect that the ball would take onlytwice as much time to roll that far.You see how the relationship works?Let's compare the ratios here.The ratio of 40 to 10, in other words, the ratio of the distances.Let me write it this way.The ratio of distance to distance 1 is 40 centimeters to 10 centimeters.The number is 4.How about the ratios of time?We look at the ratio of time,"T-2" to "T-1," see that thisis two seconds divided by one second, the ratio is 2.What's the relationship between the numbers 2 and 4?Well, it's obvious isn't it that 4 is equal to 2 squared.So, what we're seeing here is that the distance traveled is inproportion not to the time itself, but the square of the time.In other words, the distance is proportional to the square of the time.

Now this is something that's very easily testablewith an experiment because you can simply roll the ball down the plane.You can let it roll for a certain distance or it's much easierto control this actually if you let it roll for a certain time.Keep track of the data, distance and times and then simplycompare the numbers to see if these ratios work.We'll see that you can do this on a graph and in fact some of yourlaboratory exercises we'll see how you can do thisin a graphical sort of way instead of just looking at that numbers.Now, of course, if you do this only one time, you'll find that itdoesn't work out very well because of the errorin the experiment, but you can also let the ball roll for 90 centimeters.The distance of 90 centimeters down the ramp and you wouldexpect then if the same relationships holds that itwould take 3 seconds to roll 90 centimeters.The reason why is simply because the ratio of 90 to 10 is 9and that equals 3 squared which is the relationship between the two times.

In this lesson we have explored the motivation for callingGalileo the First Scientist and for calling him the Father of Science.Along the way we encountered such bizarre things as theCerts/Miller Lite Controversy or Dilemma, and the relationshipsbetween inductive and deductive logic.Weird or not, these things are elements of the developmentof science and we must touch on them, if for no other reasonthan to provide color in what might be viewed as ableak landscape of names and dates.That's not our only reason.These are aspects of human nature.They both drive and impede the process of science and ourgeneral understanding of ourselves, our universe,and the relationship between them.We reviewed Galileo's resume.We searched for those events which helped to shape himinto one of the most influential scientists ever, exerting aninfluence which will have an impact as great or maybe evengreater than that of Pythagoras, Socrates,Plato and Aristotle, Hipparchus and Ptolemy.If those names don't sound familiar, you better put downthe Discman, turn off the TV and go back to those early lessons.

In the final section of today's program we examined the toolsthat Galileo used for the first time, noting not just the toolsof logic, experiment, mathematics and logic, but also the methodswhich have become standard operating procedure for scienceof all kinds, physical science and otherwise.I hope you get an understanding nowof Galileo and put this in perspective.And looking back on Galileo, in putting him in perspectiveof the times, we see how important the character of Galileo was.Not just the ideas, not just the experiments, not just themethods, but the required someone who had the audacity and thebrusqueness to simply go against the Churchand make sure these ideas were known to people.Who knows what would have happened if Galileo or someonelike him hadn't come along at that particular time in history.It's funny when you look back in history.It almost seems as if things were destined to happen the way they happened.We don't know whether they were or not, but it seems like that.

In the next lesson we will focus on the specifics of Galileo's methods.We'll repeat some of the things that we did today and we'll lookat the discoveries he made and the brilliantconclusions he was able to draw from them.So, now we're actually ready to see Galileo's experimentsand the results which led him to the principle of inertia and thefirst real understanding of projectile motion.We'll do all that in the next program.Until then, remember, when it comes to science, get physical.So, anything to add to that, my silicon friend?Silico: "I can see how Gal Lee Lay Oh must have been frustrated,but why didn't he just to on a talk show and tell his story?"Check your timeline, they didn't have talk shows then.Wait a minute, when do ever you watch talk shows?You been jacking in to the cable feed again?We talked about that before.I don't want you doing that until I install your V-chip....Music