Galileo Galilei: Master of Science and Self-Promotion

Galileo’s career started in a monastery in Florence; but his father saw a doctor in him. Defying his father, he studied mathematics instead of medicine. He made his first invention at 22. At 25, he was lecturing at the University of Pisa and building high class musical instruments. He had to move to Padova after being mobbed out from Pisa.


Galileo Galilei was born in Pisa in 1564; he was the first child of Giulia degli Ammannati and Vincenzo Galilei. Despite his father coming from a thoroughly reputable patrician Florentine family, money was notoriously in short supply. Vincenzo was a cloth merchant but provided additional income as a musician to feed the family as it grew. Galileo would have six siblings that survived infancy. Vincenzo Galilei was also an expert in musical theory and developed the mathematical theory on the correlation of string tension and pitch.


Galileo was 10 when Vincenzo decided to relocate the family to Florence to try his luck there. At the age of 15, Galileo entered a monastery as a novice. He gained his first experiences in astrology there; and monastic life suited him as well. But becoming a monk was not intended for him as his father had other plans for him. Vincenzo had decided that he should become a doctor. It would provide Galileo with a good income and enable him to financially support the rest of the large family. 


In 1581, Galileo Galilei moved to Pisa where he enrolled as a medical student at the university. Galileo found that it was not a subject to fascinate him. He broke off his studies to devote his time to other things. During his medical studies he had already attended interesting lectures on mathematics. He began to dedicate his time entirely to this science and specifically to geometry. The respected scholar Ostilio Ricci heavily influenced his early development in the field. Ostilio Ricci was a teacher for mathematics in Florence and worked as an engineer and ballistics expert for the Medici Grand Duke of Tuscany. 


Galileo pursued his studies in Pisa until 1585. He read with the local mathematicians and conducted his own first experiment on oscillation. He got fascinated with pendulums; a fascination that would accompany him through life. He didn't graduate in Pisa but returned to Florence all the same. He continued to study and earned some money giving private lessons. His patrons arranged select readings where he presented his ideas; in consequence his name became well known in a select and elitist circle of aficionados. He had sufficient time to make his first invention, though; the hydrostatic balance was able to determine with precision the specific gravity of an object.


This doesn't sound like rich pickings; indeed, his situation could be summed up as no job, no money, and a lot of (scientific) nonsense in his head. But Galileo had caught the attention of Guido del Monte Baldo who read mathematics at the University of Pisa. Galileo therefore returned to Pisa in 1589 as an assistant to Monte Baldo, holding lectures for his students and assisting them in their studies. Besides that, he had ample time to pursue his own studies and experiments. His wages were very small inducing him to build and sell excellently crafted musical instruments.


At that time, he invented a thermometer, not a very exact one but still a working item. Through Monte Baldo and his involvement in fortifications and ballistics, Galileo Galilei became interested in the movement of bodies and especially in free fall. In the 4th century BC, Aristotle had formulated the theorem that heavy objects fall to earth faster than light ones. Like many other Aristotelian theories, this one was made an irrevocable law by Christians without trying or proving it.


Galileo’s experiments showed that Aristotle was wrong. As time keeping was out of reach, he did tests on an inclined plane. This allowed him to measure the speed of a slowly accelerating sphere. He was thereby the first to find the distinction between speed and acceleration in modern times. It led to his law of falling bodies in a vacuum which would be improved upon by Isaac Newton. His description of the experiments he conducted is an early guideline on how to communicate experimental settings to make it possible for others to replicate them. Something modern ‘science’ has forgotten how to do in favor of monetary greed.


Presenting his results to his colleagues in Pisa meant challenging Aristotle; his presentation was ridiculed by the kindly, damned by the righteous, and outright rejected by most. His welcome in Pisa had come to an end and his contract as a lecturer was not prolonged. In the eyes of the establishment, he had not only committed a scientific solecism, he had committed an outright crime against science and the church.


Meanwhile, Galileo had established himself with several high placed admirers and acquired powerful protectors; he was offered the chair of professor for mathematics in Padova due to their intervention. The great Giordano Bruno had been expected to be called to that post. The pay was definitely better than in Pisa, but Galileo still gave paid exclusive lectures for a select circle of people. He also presented and sold a precursor to the slide rule called a compass. To that end he employed a full time mechanical engineer in production.


In Padova, he rekindled his interested in astronomy and cosmology. In a letter to Johannes Kepler in 1597, he expressed his belief in the heliocentric theory of Nicholas Copernicus. At the same time, he was completely unimpressed by the writings of Tycho Brahe on comets. He missed the point of Brahe’s discovery completely, calling comets ‘ape stars’.


In 1608, the States General in The Hague (the governing body of the Netherlands) was trying to unravel the puzzle over a patent. Subject of contention was a tube containing two lenses that allowed a magnified view of distant objects; it would become known as a telescope. German lens maker Hans Lipperhey resident in Middelburg had submitted the request for a patent at the same time as Dutch lens maker Jacob Metius from Alkmaar.


The States General took a practical way out of the dilemma by not granting a patent to either of them ‘as the device could be copied too easily’. The approach was a sensible one considering that Dutch lens maker Sacharias Janssen of Middelburg was at the same time already selling his device at the Frankfurt Fair. All these devices were able to magnify distant objects by a factor of three or four.


The telescope went viral in the world of science. Within months, it was in use all over Europe. Within a year, Galileo Galilei was holding one in his hands in Italy and decided to improve on it. He quickly designed one that could magnify by a factor of eight. He magnanimously offered his 'invention' to the Signoria in Venice (his employers in Padova) for commercial exploitation and received a handsome increase in his income from their hands. During his presentation, he somehow forgot to mention that his own employees in Padova were already constructing one with a magnifying factor of 20.


When he was going for a factor 33 not much later, Galileo Galilei was way ahead of any competition. He observed the moon, provided a description of its irregular surface, and made drawings of it and the lunar terminator. The treatise and the drawings were a clear breach with Aristotle who had asserted that the moon was immaculate. He then turned his eyes outward and discovered four of Jupiter’s moons (or maybe rediscovered them). With an eye to the court of Florence he called them the Medici moons.


In 1610, he published the Sidereus Nuncius describing all his findings since he started using the telescope. Astronomers all over Europe were bowled over by the publication and heaped Galileo with praise. They all had a major problem, though; they could not really verify his findings. Galileo’s sprint for a telescope with a magnifying power of 33 had given him a technical advantage; his technical superiority is comparable to the difference between a Ferrari and a Volkswagen Beetle.


His technical advantage evaporated a year later when the other astronomers in Europe were catching up. But it didn't matter to Galileo anymore. As planed by him over the Medici moons, he had been appointed resident mathematician and philosopher to the ducal court in Florence and First Professor for Mathematics in Pisa. The latter post came without teaching schedule, thus leaving him free to pursue his studies. This appointment was made by Cosimo II de Medici, who had become the Grand Duke of Tuscany in 1609; Cosimo had been Galileo’s student from 1605 to 1608.


In 1611, Galileo was invited to Rome for an audience with Pope Paul V. Galileo was offered the unique possibility to present his theories to the Pope and his prime helper Cardinal Maffeo Barberini; and Cardinal Barberini was a supporter and friend of Galileo’s. Galileo arrived at the audience armed with sensational material; but each and every one of his spectacular discoveries was loaded with enough dynamite to blow the roof off Saint Peter’s Basilica. The Pope was impressed and interested in his theories; just as long as they remained theories, the world would be in good order.


Galileo returned to Florence laden with the goodwill of Pope Paul V and his first Cardinal. He also became a member of Marchese Federico Cesi’s Academia Lynceorum. As his technological advantage had evaporated, he now turned his eyes to a new subject: The sun. He got into a lengthy and pointless discussion with the German Jesuit priest Christoph Scheiner over who had first discovered sun spots. Galileo wanted to see clouds as the cause for these spots; Scheiner thought that stellar objects were responsible. Cesi’s academy paid for the publication of Galileo’s On Sunspots.


Apart from quibbling, these discoveries and others made by other astronomers all over Europe drove Galileo to the conclusion that the heliocentric view was the only acceptable one. He started to voice his opinion on that more and more and often quite publicly. With this publicity, he started to interfere with the interests of the Catholic Church.


In 1612, Galileo was able to prove Aristotle wrong in the field of physics. Aristotle had taught that ice swam on water because it was flat. Immersing round ice balls into water and finding them swimming he showed that ice was lighter than water irrespective of shape. Ever the showman, he carried off that little stunt in front of Cardinal Barberini.


Being scientifically right might be nice, but it didn't win him any friends. Contrariwise, the hell hounds were closing in on him. In 1615, he was denounced in front of the Inquisition by the Dominican priest Niccolo Lorini because of his Copernican views. He was ordered to Rome by Pope Paul V and had to appear before the saintly Cardinal Bellarmine; he was let off with a rap on his knuckles and with the stern reminder to keep his opinions to himself.



He took the warning seriously, especially when only months later the writings of Copernicus and many other astronomers were put on the index. Instead of making a public nuisance of himself, he concentrated on his research. While his theory on sun spots being clouds was not a success, neither were his explanations that Earth was moved by the Trade Winds or that the tides were caused by the movement of Earth (much like slopping about milk in a bucket).


In 1623, Pope Paul V died. The College of Cardinals chose Cardinal Barberini as his successor who chose the Papal name of Urban. The new Pope Urban VIII had followed Galileo’s research closely and with favor. Galileo supposed that this would mean the time for a more open approach to science had begun. He used the occasion to dedicate his new book Il Saggiatore to the new Pope. The book was a badly concealed attack on the comet theories of Tycho Brahe and astrologers thinking along the same line; Galileo hadn't observed any of the comets passing and based his reasoning on Aristotle’s teachings alone.


1624 saw him in Rome no less than six times to confer with the Pope and various Cardinals. The Pope’s wish was a book about the Copernican system treating it as a mathematical hypothesis. The book obviously would conclude proving the obvious superiority of the geocentric system. After some research and having finished off some other loose ends, Galileo got to writing just a few months later. Unlike many of his contemporaries, Galileo chose not to write in Latin. His comparison of the Copernican and the Ptolemaic system was intended for self advertisement as much as to gratify the Pope; this was much better done in Italian.


It took him six years to complete the work; and then he didn't receive the Imprimatur from the Inquisition. The Cardinals thought that Galileo’s boot licking abilities had flagged and that the hypothetical character of Copernicus’ views was not expressed adequately. They made him rewrite the introduction several times until finally agreeing to let it pass. 1632 finally saw the book coming from the print presses; and it became the year’s best seller.


The unexpected success triggered suspicion, and Pope Urban VIII had the book re-examined by the Inquisition. It was put on the index, and the case file Galileo Galilei was re-opened with the Cardinal Inquisitor. It ended in house-arrest for Galileo Galilei and a prohibition of publishing any further theses or theories of his.


The irony of Galileo Galilei's life is the fact that his own self marketing today is perceived as the important part of his biography. All his important discoveries on the other hand are almost forgotten. He is remembered for the invention of the telescope and the compass, two things he didn't do; he is also remembered for the discovery of four moons of Jupiter, something he probably didn't do either. And later legend has him throwing rubbish from the tower of Pisa, something he definitely didn't do. That he brought physics back from where the church had frozen it on the authority of Aristotle and invented the scientific process for conducting and describing experiments in a way to allow others to replicate them is almost forgotten.


Further reading