by Mario Livio
what we call today the scientific method: A good discussion of Galileo’s contribution is in Gower 1997, 21.
Art historian Heinrich Wolfflin: Wolfflin 1950, cited also in Machamer 1998.
Galileo scholar Giorgio de Santillana: Of particular interest is Santillana 1955, which attempts to follow Galileo’s mental journey.
“Those who study the ancients”: Leonardo da Vinci, cited in Nuland 2000.
Viviani further tells us: Viviani 1717. An English translation that includes other early biographies, documents, and annoations is Gattei 2019.
Giorgio Vasari, in his biographies: Vasari 1550.
Galileo himself played the lute: On Galileo’s interest in music, see Fabris 2011.
Galileo could recite at length: Good descriptions of Galileo’s love for literature and art are in Panofsky 1954 and Peterson 2011.
All of these discoveries created: Machamer 1998 gives a brief, good summary of the background against which Galileo was operating. A superb description of the entire scientific culture of the time is in Camerota 2004.
Was the rise of individualism: Russell 2007 explains this trend well.
The invention of movable type: Described nicely in Eisenstein 1983. The transport of information is discussed in Reeves 2014.
“the discovery of the world and of man”: In Michelet 1855, vol. 7–8 Renaissance et Réforme.
Einstein said about this book: Einstein 1953.
“A good many times I have been present”: Snow 1959. The talk was delivered on May 7, 1959, in the Senate House in Cambridge. In 1963 Snow published an expanded version entitled The Two Cultures: A Second Look, in which he was more optimistic about bridging the gap between the two cultures.
“History of Science, far from serving”: Wootton 2015, 16.
John Brockman introduced the concept: Brockman 1995. Originally published online in 1991 at Edge (edge.org).
“the unreasonable effectiveness of mathematics”: Wigner 1960.
CHAPTER 2: A HUMANIST SCIENTIST
was born in Pisa on February 15 or 16: Galileo’s date of birth is given more often as February 15, 1564, but two horoscopes for himself in his own hand are for February 16 and only one for February 15. Swerdlow 2004 gives a nice discussion of the horoscopes.
Vincenzo apparently also became a part-time: This is not certain. Vincenzo did accept part of Julia’s dowry in the form of clothes.
had two more sons and three: Galileo’s brothers were Benedetto and Michelangelo. His known sisters were Virginia, Anna, and Livia. It is unclear whether Lena was also a sister or a domestic. In Opere di Galileo Galilei, Vol. 19, Documenti.
Dialogue on Ancient and Modern Music: The book by Vincenzo Galilei was published in Florence in late 1581 or early 1582. A translation is V. Galilei 2003.
the idea of using pendulums for measuring time: This interesting speculation was raised by Drake 1978.
second biographer, Niccolo Gherardini: He was Galileo’s neighbor in Rome in 1633. In conversations with Galileo, Gherardini gathered some biographical material, which he later summarized.
in September 1580: Almost all biographies give 1581, but Camerota and Helbing 2000 demonstrate convincingly that it was 1580.
Tuscan court mathematician Ostilio Ricci: Ricci became mathematician to Grand Duke Ferdinando I, but this was at a later period.
“If Euclid failed to kindle”: Einstein 1954.
“One could travel securely”: Cited in Peterson 2011.
“How is it possible that mathematics”: Einstein 1934.
a small scientific tract entitled La Bilancetta: An English translation of the essay is in Fermi and Bernardini 1961.
Treatise on the Sphere, or Cosmography: This treatise was published posthumously by the priest Urbano d’Aviso.
mapping Dante’s disorienting description: The mathematical “plans” for hell are beautifully discussed in some detail in Heilbron 2010.
Galileo wrote in Two New Sciences: Galilei 1638.
“If being a prodigy is not a requirement”: Csikszentmihalyi 1996.
CHAPTER 3: A LEANING TOWER AND INCLINED PLANES
as a professor and chair of mathematics: A good description of Galileo’s Pisan studies is in Wallace 1998.
later biographers and historians just kept adding: English language and literature professor Lane Cooper collected some of these stories and discussed the Leaning Tower experiment. His work has been criticized in the past, but it remains an honest effort to examine experiments in free fall. Cooper 1935. Michael Segre expertly reviews the story in Segre 1989. Camerota and Helbing 2000 beautifully discuss the background.
Most present-day historians of science think: Renowned Galileo scholar Stillman Drake thought that the demonstration did take place. Drake 1978.
at the forefront of both experimental and theoretical investigations: In a series of highly influential works, science historian Alexandre Koyré argued that Galileo could not have obtained the experimental results he described later in Two New Sciences using his equipment (for example, Koyré 1953, 1978). These claims have been completely refuted by Thomas Settle (Settle 1961), James MacLachlan (MacLachlan 1973), and Stillman Drake (Drake 1973). See also Clavelin 1974. The distinction between Galileo’s experientia (experience in general) and periculum (experiment or test) is discussed in Schmitt 1969.
This peculiar result has been shown: For example, Thomas Settle repeated the experiment in front of a camera. Settle 1983.
De Motu marked the beginning: Galileo 1590; trans. Drabkin and Drake 1960 and Camerota and Helbing 2000 give excellent descriptions of Galileo’s and other Pisan professors’ ideas and experiments on falling bodies. See also Wisan 1974.
‘A hundred-pound iron ball’: Galilei 1638.
Apollo 15 astronaut David Scott: Can be seen at NASA online, last modified February 11, 2016, https://nssdc.gsfc.nasa.gov/planetary/lunar/apollo_15_feather_drop.html.
“When a person has discovered the truth”: Cited in Drake 1978.
his interest in philosophy: Wallace 1998, Lennox 1986, and McTighe 1967.
Here are a few lines from the controversial poem: The poem was translated into English by astronomer Giovanni Bignami. Bignami 2000.
from 1603 to 1609: Geymonat 1965 and Heilbron 2010 give excellent descriptions of the Paduan period in Galileo’s life.
a few of his groundbreaking results: Weinberg 2014 gives an excellent description of the importance of Galileo’s pioneering experiments.
“In a small height”: In Opere di Galileo Galilei, Vol. 8, p. 128, cited in Drake 1978, 85.
“Clearly a statement cannot be tested”: Eddington 1939.
The research concerning climate change: Michael Mann has given an excellent description of the problems involved in a series of publications. Mann 2012a is a must-read. Another clear exposition is Romm 2016.
Casting occasional horoscopes for students: Galileo’s totally dismissive opinion on astrology is mentioned in a letter from the archbishop of Siena, Ascanio Piccolomini, to his brother Ottavio on September 22, 1633. Bucciantini and Camerota 2005.
One in particular, Gianfrancesco Sagredo: Nick Wilding wrote a brilliant book about Sagredo. Wilding 2014.
If I sometimes speculate about science: In Opere di Galileo Galilei, vol. 12, pp. 43–44.
in addition to being a prelate, a historian: David Wootton wrote a captivating account about the fascinating personality of Paolo Sarpi. Wootton 1983.
of the processes involved in vision: An interesting book on the role of vision in Galileo’s discoveries is Piccolino and Wade 2014.
the geometric and military compass: Galileo’s instrument allowed one to perform arithmetic calculations and geometrical operations. The story of the compass is described, for example, in Bedini 1967. The website of the Galileo Museum in Florence contains beautiful images of the instrument and the booklet about it. Galileo instructed dignitaries such as Prince John Frederick of Alsace and the Archduke Ferdinand of Austria how to use the instrum
ent. See “Instruments: The Tools of Science,” www.museogalileo.it/it/biblioteca-e-istituto-di-ricerca/pubblicazioni-e-convegni/strumenti.html.
Two elements in particular stand out: Maurice Clavelin, in The Natural Philosophy of Galileo, referred to Galileo’s contribution as the “geometrization of motion.” In other words, not only that motion is interpreted in terms of quantitative laws but also that an entire body of established theorems and propositions is presented as a coherent whole. Clavelin 1974.
The first letter, dated May 30, 1597: Galileo added that if Mazzoni was satisfied with Galileo’s argument, “the opinion of those great men [Pythagoras and Copernicus] and my own belief may not remain desolated.”
after having read only the preface of the book: Because Kepler’s emissary, Paul Hamberger, was about to immediately return to Germany. Rosen 1966.
Galileo bothered to answer only a few: One of those, Antonio Lorenzini, was expressing the doubts of philosopher Cesare Cremonini about the validity of parallax determinations. However, Lorenzini’s criticism was on technical grounds—an area in which his knowledge was minimal. Galileo replied only because Kepler urged Italian astronomers to do so.
composed with friends and published: The pseudonym was Cecco di Ronchitti, and the dialogue was written in a dialect common in the Paduan countryside. The entire episode is described in detail by Heilbron 2010, 123–25.
“To obtain any salary from a Republic”: Opere di Galileo Galilei, vol. 10, p. 233.
“I desire that the primary intention”: In a letter to Belisario Vinta, the Tuscan state secretary to the grand duke.
CHAPTER 4: A COPERNICAN
“About 10 months ago”: Excellent translations of the Sidereal Messenger are by Drake 1957, 27, and Van Helden 1989.
“that a certain Fleming”: The Dutch Hans Lippershey applied for a patent for a telescope in 1608.
“the Maker of the stars himself”: In Van Helden 1989, 31.
of Federico Cesi’s Accademia dei Lincei: Mario Biagioli gives a fascinating description of the social and cultural atmosphere associated with patronage, and Galileo’s relation with Cesi and the Accademia dei Lincei. Biagioli 1993. I am grateful also to Stefano Gatti for helpful information on Cesi.
that mountain to be more than four miles: Given the limited quality of the data at the time, the estimate was not bad, but see also Adams 1932.
When we compare Galileo’s Drawings: Galluzzi 2009 gives a detailed comparison of Galileo’s drawings with modern observations.
The Flight to Egypt: The painting is in the Alte Pinakothek, Munich. For an interesting essay about the painting, see McCouat 2016. An online reproduction of the painting (which can be enlarged to see the lunar details) is at https://upload.Wikimedia.org/Wikipedia/commons/l/le/Adam_Elsheimer_-Die_Flucht_nacht_Ägypten%28AltePinakothek%29.jpg.
by his friend Federico Cesi: Elsheimer was a good friend of the German doctor and botanist Giovanni Feber, who in addition to being Cesi’s friend, became a member of the Accademia dei Lincei in 1611.
An intriguing story related: The entire affair was described beautifully by Nicholas Schmidle in the New Yorker. Schmidle 2013.
“If we examine the matter more closely”: In The Sidereal Messenger, Van Helden 1989, 53.
“What is so surprising about that?”: Ibid., 55.
“she is movable and surpasses the Moon”: Ibid, 57.
“A great and wondrous sign appeared”: Revelation 12:1.
broke up into countless faint stars: In Galileo’s words in Sidereal Messenger: “the multitude of small ones is truly unfathomable.”
Being well aware of Bruno’s tragic end: Hilary Gatti published an interesting collection of essays on Bruno’s richly diverse interests. Gatti 2011.
recent estimates of the number of roughly: For example, Petigura, Howard, and Marcy 2013.
“Since they sometimes follow”: Sidereal Messenger, Van Helden 1989, 84. William Shea 1998 and Noel Swerdlow 1998 give excellent summaries of Galileo’s discoveries with the telescope and their implications for Copernicanism.
A true explanation for the strange ears: In the 1640s, Johannes Hevelius and Pierre Gassendi made many observations of Saturn. Hevelius and the famous architect Christopher Wren proposed incorrect models in 1656 and 1658, respectively. Huygens’s suggestion of a flat ring appeared in his book The Saturnian System, which was published in 1659. Collected in Huygens 1888, vol. 15, 312. See also Van Helden 1974.
between October and December 1610: Gingerich 1984 and Peters 1984 discuss the phases of Venus.
“Far from the least important”: Clavius 1611–12.
in the preface to his book Bodies in Water: The translation of the book by Thomas Salusbury was edited by Stillman Drake. Galilei 1612.
History and Demonstrations Concerning Sunspots: An English translation appears in Drake 1957, 89.
Galileo moved on to dismantling: Bernard Dame 1966 presents the entire affair surrounding the controversy over sunspots. Dame 1966. See also Van Helden 1996. Translated excerpts from the three letters to Welser, with an introduction, appear in Drake 1957, 59.
“The eternal mystery of the world”: Einstein 1936.
CHAPTER 5: EVERY ACTION HAS A REACTION
Galileo claimed that his new device—the telescope: Spectacular images are in Galluzzi 2009.
“Let us conclude, therefore, that he”: Coresio 1612, cited in Shea 1972.
“Before we consider Galileo’s demonstrations”: In di Grazia’s Considerazioni (1612), which was reprinted in A. Favaro’s Opere di Galileo Galilei, vol. 4, p. 385.
“As if geometry in our day”: From Discourse on Bodies in Water, cited in Shea 1972.
wrote to Christopher Clavius: Welser wrote from Augsburg, Bavaria, on March 12, 1610, one day before the Sidereus Nuncius was published. In Galluzzi 2017, 5.
Giovanni Bartoli, wrote on March 27: Cited in Heilbron 2010, 161.
“His hair hung down”: A letter of Horky to Kepler on April 27, 1610. In Opere di Galileo Galilei, vol. 10, pp. 342–43.
“The conclusion is quite clear. Our Moon exists”: Kepler wrote this in his Dissertatio cum Nuncio Sidereo of 1610.
“Having presented to Her Majesty”: Cited in Bucciantini, Camerota, and Giudice 2015, 168.
“But you, O Galileo”: Ibid., 190.
Assumption of the Virgin: Finer details of the lunar surface in this fresco can be seen online at: Flickr, accessed July 16, 2019, www.flickr.com/photos/profzucker/22897677200
not as a smooth: Booth and Van Helden 2000 give a detailed discussion of the depiction of the Moon in paintings.
“It is true that with the spyglass”: Opere di Galileo Galilei, vol. 11, pp. 92–93. Cited also in Van Helden 1989, 111.
Ironically, some climate change deniers: For a discussion of the fallacy involved in the Galileo gambit, see, for example, Mann 2016.
Some 400 books: Of 405 books, 234 were Italian, 56 French, 43 German, 22 English, and 50 from other countries. Of these, 160 were favorable to Galileo, 114 unfavorable, and 131 generally neutral. Drake 1967.
The name was suggested by theologian: Rosen 1947, 31.
now known as the “Copernican principle”: For an explanation, see, for example, Livio 2018.
about 120 letters: All described and analyzed beautifully by Sobel 1999, and translated and edited in Sobel 2001.
he wrote his long and detailed Letter to Castelli: Maurice Finocchiaro’s translation of the slightly revised letter appears in Finocchiaro 1989, 49–54, and in Finocchiaro 2008, 103–9. In the Opere di Galileo Galilei, it is in vol. 5, pp. 281–88. In 2018 the original version was discovered. See description in chap. 6.
“proved himself more perspicacious”: Cited, for example, in Frova and Marenzana 2006, 475.
“there is more ado to interpret”: Appears in the essay entitled “Of Experience,” online at: www.gutenberg.org/files/3599/3599.txt.
CHAPTER 6: INTO A MINEFIELD
Galileo took the first, insightful step: For a di
scussion of Galileo’s achievements, see also Shea 1972; Brophy and Paolucci 1962.
a model invented so as to “save the appearances”: Many authors have discussed Galileo’s interaction with the Church. In addition to sources mentioned already, here are a few more that I found very helpful: Blackwell 1991, Finocchiaro 2010, and McMullen 1998.
Even as late as 1945: See chap. 16 for more details on this episode.
There has been a fascinating: The story is beautifully described in Camerota, Giudice, and Ricciardo 2018.
“I am most displeased that the ignorance”: Castelli wrote this letter on December 31. For a more complete text, see, for example, Drake 1978, 239.
the current climate change deniers: It is important to clarify that atmospheric physicist Richard Lindzen, who is often described as a climate change denier, does not deny the reality of climate change. He is only not convinced about the role of humans in producing it, and about the actions that are proposed to be taken to solve the problem. An overwhelming majority of the scientific community disagrees with Lindzen. For a very brief summary of the current thinking regarding climate change, see, for example: “Climate Change: Where We Are in Seven Charts and What You Can Do to Help,” BBC News online, last modified April 18, 2019, www.bbc.com/news/science-environment-46384067. See also Schrag 2007. For Lindzen’s minority opinion see, for instance, Lindzen, “Thoughts on the Public Discourse over Climate Change,” Merion West, last modified April 25, 2017, https://merionwest.com/2017/04/25/richard-lindzen-thoughts-on-the-public-discourse-over-climate-change.
“he [Barberini] would like greater caution”: The letter from Ciampoli to Galileo was dated February 28, 1615. In Opere di Galileo Galilei, vol. 12, p. 146. A good description of the events is given in Shea and Artigas 2003 and in Fantoli 2012.
Bellarmino suggested further that Galileo: Described in detail in Blackwell 1991, 73.
“Scripture serves us by speaking”: Foscarini’s publication appears as app. 6 in Blackwell 1991. The citation is from p. 232.