The Life of Copernicus
by Pierre Gassendi with notes by Olivier Thill

A New Biography Timeline Achievements Uncertainties and Errors Bibliography

Table of contents
His Real Life, Not a Novel - A 17th Century Text With 21st Century Notes
His Name - Place and Date of Birth - The End of The Middle Ages - His Astrological Theme
His Family - On His Paternal Side - On His Maternal Side - His Childhood in Thorun - The Death of His Father - The Career of Uncle Lucas - At Cracow University - At Bologna University - At Padua University
Varmia, Borussia - The Years 1503-1509 - The Teutonic Knights - Copernicus' First Published Book in 1509 - The Years 1510-1516
His Books of Medicine - The Consultations of Doctor Copernicus - The Leper of His brother
Cartographer - Meditata - The Bread Tariff and The Baking of Bread
Administrating the properties of the chapter - The War Against The Teutonic Knights - Popes and Bishops
Contemplation and Study - The Pythagoreans - Aristarchus of Samos, Copernicus of antiquity - Astronomical Tables
The Quadrant - The Rulers - The Armillary Sphere - The accuracy of His Instruments
Commentariolus - The Letter Against Werner
Orbs - Looking at The Coast from The Ship - Gravity - Size of The Universe
The Three Motions of The Earth - The Catalog of Stars - The Precession of The Equinoxes - The Moon and The Planets
The Council of Lateran - The Council of Trent - Clavius - Cardinal Schönberg
CHAPTER 1. NARRATIO PRIMA Rheticus - Giese - Narratio Prima - The Discourse of Prussia - De Triangulorum
Just Before The Printing - The Homocentric Authors - The Preface to The Pope Paul III - Osiander Adds a Warning to The Readers - He Dies The Day He Sees His Book
A Good Man - Love Affairs - His Library
Paintings - His Epitaph - Tycho Brahe's Homage - Selected Odes
Petrus Ramus - Erasmus Reinhold - Michael Maestlin - Petrus Pitatus - Johannes Stadius, The Belgians - Other authors of Ephemerides - Copernicans - Anti-Copernicans
From 1543 to 1616 - The Decrees of the Holy Congregation - Bruno and Vanini - Magnetism - Tides - The phases of Venus - The Satellites of Jupiter
Falling Bodies - The Pendulum of Calignon - The Pendulum of Foucault - Other Means
GASSENDI (1592-1655)
Life of Gassendi - Gassendi and His Troubles With an Astrologer - Gassendi and The Printing of Galileo's Dialogo - Preface by Gassendi
A New Biography

ISBN 1-591601-93-2, Xulon Press, available at

The 360 pages of this book presents, for the first time in English, the biography of Copernicus written in the 17th century by Pierre Gassendi, completed with annotations and additions from the latest pieces of information found in the archives.


ca. 1473Nicolaus Copernicus is born at Torun, Poland.
ca. 1483The father of Copernicus dies.
1489Lucas Watzenrode, the maternal uncle of Copernicus, is elected Bishop of Warmia.
1491Nicolaus Copernicus and his brother begin to study the Liberal Arts at the University of Krakow.
1495Copernicus obtains the 14th canonry of Warmia.
1496-1503Copernicus studies law and medicine in Italy.
ca. 1503-ca. 1510Copernicus lives with his uncle in the episcopal castle of Warmia at Heilsberg/Lidzbark Warmiñski. In 1507 he is officially appointed physician of the bishops of Warmia.
1509Copernicus' fisrt published book is a Latin translation of the aphorisms of Theophylactus, who was a historian and Egyptian poet of Greek culture, living in the seventh century A.D.
ca. 1510-1543Copernicus lives with most of the other 16 canons of Warmia residing in Frauenburg/Frombork.
1509-1529Copernicus writes his main book, De revolutionibus where, among other things, he records 27 astronomical observations he has made in these years. In 1515, he is particularly busy with the determination of the precise length of the year, in order to bring a contribution to the commitee of the Lateran Council which is working on the reform of the calendar.
1516-1519Copernicus is appointed Administrator of the chapter. He will carry other administrative duties at other times, but these years are memorable because the registers have been preserved.
1517-1528Copernicus works on the reform of the Prussian currency.
1520-1521On 1 January 1520 the Teutonic Knights invade Warmia. From October to November 1520, they besiege the castle of Allenstein/Olsztyn, Copernicus is the highest authority staying inside. A peace treaty is signed in April 1521.
1539Rheticus, Professor of Mathematics at Wittenberg University, visits Copernicus in Frauenburg.
1540An abridged version of Copernicus’ works on astronomy is written by Rheticus, and published as Narratio prima at Danzig/Gdansk
1542Copernicus’ book on Trigonometry, De Lateribus et Angulis Triangolorum is published at Wittenberg.
1543Copernicus’ book, De Revolutionibus Orbium Coelestium is published at Nuremberg. Copernicus dies in May 1543.
1616In Rome, the Congregation of the Index asked for the correction of 11 lines in Copernicus’ book, De Revolutionibus and condemns the Copernican doctrine.
1633Galileo is trialed, because, his latest book, Dialogo sopra i due Massimi Sistemi del Mondo, Tolemaico, e Copernicano supports the prohibited Copernican doctrine.
1635Galileo's Dialogo is translated in Latin and published by Gassendi and his friends, who have also obtained comfortable retiring conditions for Galileo.
1837At Königsberg, Friedrich Wilhelm Bessel, detects a stellar parallax. This proves the motion of the earth around the sun.
1851At Paris, Jean Bernard Léon Foucault explains the deviation of his giant pendulum by the daily rotation of the earth, according to the mathematical model enunciated in 1831 by Gaspard-Gustave de Coriolis.


Copernicus' main achievement is the presentation of the triple motion of the earth:

- the daily motion around its axis;
- the yearly motion about the sun;
- and the motion called the precession of the equinoxes.

Copernicus knew that Aristarchus of Samos and Jean Buridan already thought of the motion of the earth, but the work of Aristarchus has been lost, and Buridan rejected this idea, beause he did not dare go against the authority of Aristotle. Copernicus convinced the scientific world of the seriousness of his idea by the earnestness of his study, and the credit he gained by the great probity of his life.

Copernicus have also imagined that the planets and the sun are linked by the force of gravity, rather than by a would-be natural tendency to a circular motion of objects beyond the moon, as it was thought by Aristotle and others, or rather than by the magnetic force, as it was thought by William Gilbert and others.

Copernicus was a very good physician, compared to the other physicians of his time. He cured or alleviated the pains of many people.

Copernicus' work on the reform of the Prussian coinage was certainly very positive.

Copernicus, with Giese, and other moderate clergymen of Warmia, contributed to ease the tensions in the region between the Roman Catholics and the Protestants.

Copernicus was a relatively good administrator.

Copernicus' translation of the aphorisms of Theophylactus was not a success, since very few people read his book.

Copernicus did not succeed in improving the Alfonsine tables of the stars and planets. Owen Gingerich and Jerzy Dobrzycki have shown that there is no clear winner between the Alfonsine Tables, the Copernican Tables, and the Prutenic Tables of Reinhold. Astronomers will have to wait for the Rudolphine Tables of Tycho Brahe and Kepler in order to see a significant improvement over the Alfonsine Tables made in the Middle Ages.

Uncertainties and Errors

His date of birth is not known with certainty.

- 19 February 1473 (Julian Calendar) is the date proposed by Paul Eber (1511-1569) in Calendarium historicum. He is followed by Michael Maestlin (1550-1631), Gassendi, and the vast majority of modern biographers. This date appears also on the copy of the drawing of an horoscope which was found at the end of the 19th century by Birkenmajer.
- 10 February 1473 is proposed by Caspar Peucer (1525-1602), in Elementa doctrinae de circulis coelestibus et primo motu.
- 4 February 1473 is proposed by Johannes Gartze, or Garcaeus, (1530-ca. 1574) in Astrologiae methodus.
- 19 January 1472 is proposed by Francesco Giuntini, or Junctinus, (1523-1590) in Speculum Astrologiae.


The date of his death is not known with certainty.

The date usually retained is 23 May 1543. This date was noted by Giese in a letter to Rheticus. But Giese was not near his friend when he died. Besides, on 7 May 1543, Gaspar Hoge, provost of the parish church in Frauenburg, as attorney of Johannes Loitsch, asked the chapter to grant him canonship and prebend on the basis of a papal letter. On 21 May 1543, the chapter allowed the coadjutor, Johannes Loitsch, to replace Copernicus as a canon, as if he was already dead on May 21 (see the biography of Jürgen Hamel).


The date of the death of his father is not known with certainty.

Copernicus' father died some day, between 18 July 1483 (see Regesta Copernicana, record #18) and 19 August 1485 (see Regesta Copernicana, record #19), not necessarily in 1483 as it is often said.


His father may not have been replaced by his uncle Lucas.

There is not a single evidence showing that Lucas Watzenrode, Copernicus’ maternal uncle, was the guardian after the death of his father. In 1483, Lucas was very busy with his job, he was younger than the other two uncles of Copernicus, and unlike them, he did not live in Torun. Therefore I believe it was somebody else who took care of the children, either the semi-brother of Copernicus' mother, uncle Johann Peckaw, or the husband of the sister of Copernicus' mother, the mayor of Torun, uncle Tileman von Allen. Besides, a letter of Copernicus' brother has been found where the brother used a signet ring showing the arms of Tileman von Allen.


It is unknown whether Copernicus stayed at Rome for just one day, one week, one month or more.

The only report we have of the travel of Copernicus to Rome is given by Rheticus in a single sentence: Also, at Rome, around the year 1500, aged approximately 27, he was professor of mathematics in front of a large audience of students and an eminent circle of specialists in this branch of knowledge.
It is an overstatement to affirm that he exposed his new theory, that people in the audience remarked his brillant speech, and having been impressed, they would have invited him later to Rome to work on the reform of the calendar.


Copernicus may not have studied medecine in Padua.

At the end of 1501, Copernicus was back in Italy with his brother. They will stay until the summer or the autumn of 1503. It is said that Nicolaus studied medicine at Padua, although there is not a single document from the University of Padua attesting his presence. The only documents about Copernicus in these years are a proxy for the scholastry of Breslau/Wroclaw signed on 11 January 1503 in the episcopal chancellery of Padua, and a line in the registry of the episcopal notary of Ferrara where is recorded the obtention of the degree of Doctor decretorum of Copernicus, on 31 May 1503.


The date of the Commentariolus is unknown.

The Commentariolus is Copernicus' first written account of his revolutionary theory of the solar system. This manuscript of six leaves bears no date. Koyré said "Commentariolus is in a state of maturity which is the despair of historians". Rosen said almost the same thing: "Actually, in its admirable compactness, without a superfluous word, Commentariolus gives every sign of being the end product of much reflection, careful planning, and superb organization." Here is a list of Copernican scholars with the date they suggest for its redaction: M. Curtze, the modern discoverer of Commentariolus, between 1533 and 1539; Fred Hoyle, 1533; J. L. E. Dreyer, author of an history of astronomy, a short time before 1533; Jean-René Roy, 1530; Avram Hayli, of the observatory of Besançon, France, between 1512 and 1514; Edward Rosen and Olivier Thill (the author of this web page), between the latter half of 1508 and early 1514; L. Birkenmajer, who discovered Miechow's list, 1512; Noel M. Swerdlow & Otto Neugebauer, ca. 1510; Jan Adamczewski, Jerzy Szperkowicz, and the web page of Frombork's museum, 1507.


It seems that Copernicus worked on the reform of the calendar in 1515, rather than in 1513.

In De revolutionibus, III, 16, he declares: "I have devoted my attention to investigating these topics [length of the year], and in particular in 1515 A.D.", and elsewhere the year 1515 is mentioned five other times in relation with his search for the exact length of the year. The president of the commission for the reform of the calendar, Bishop Paul of Middelburg, mentioned the name of Copernicus among those who wrote to him in his Secundum compendium correctionis calendarij which is the second version of a treatise printed earlier at Fossombrone in 1513, Paulina sive de recta Paschae celebratione where the name of Copernicus does not appear.
Eventually, the Gregorian reform of the calendar was promulgated in 1582, and applied to Catholic countries in 1582, to Protestant countries in 1700, to Anglican countries in 1752, to Asian countries about the beginning of the 20th century. The old Julian calendar contained already leap years. The novelty was the exception on leap years every 100 years, except every 400 years. It is an overstatement to say that the new calendar is based on Copernicus's contribution, because the length of the year retained by the church is an approximation which has already been found by the Egyptians, the Greeks, and many other astronomers (see Noel M. Swerdlow, Journal for the History of Astronmy, 1986, page 110, and Edward Rosen in Isis, 32, 1958, reprinted in Copernicus and his Successors).


Copernicus was not an isolated astronomer.

Although, Copernicus himself complained of living in the most remote corner of the earth, he was not the lonely scientist who is sometimes depicted. Copernicus had big astronomical instruments that he could not hide from his colleagues, e.g. a triquetrum which is a triangle made of three sticks, 2 meters + 2 meters + 1.5 meter. Some of his fellow canons were astronomers like him. His best friend, who was a canon, and then a bishop, Tideman Giese was also an astronomer. Rheticus reports "From England had been brought to him [Giese] a gnomon really fit for a prince". His bishops knew his passion for astronomy and encouraged him, e.g. Dantiscus praised Copernicus' works to the astronomers of Belgium. Copernicus, himself, exchanged numerous letters with several astronomers.


It is a mistake to believe that Copernicus' theory would not have been known without Galileo.

Here is a list of persons who knew Copernicus' theory before 1615 and who were "Copernicans", or at least, not opposed to his system if a proof could be brought to them: Bernard Wapowski, Tiedeman Giese, Johannes Dantiscus, Nicolaus Schönberg, Johann Albertus Widmanstetter or Widmanstadt, Georg-Joachim Rheticus, Heinrich Zell, Andreas Aurifaber, Achille Pirmin Gasser, Johannes Petreius, Erasmus Reinhold, Johannes Angelus, Petrus Ramus or de la Ramée, Omer Talon, Robert Record or Recorde, John Feild or Field, John Dee, Pontus de Tyard, Leonardo Botallo, Petrus Pitatus, Johannes Stadius, Regnier Gemma Frisius, Cyprianus Leovitius, David Origano or Tost, Nicodème Frischlin, Nicolao Zoravio, Brunone Seidelius, Christian Urstitius or Wursteisen, Erasmus Oswald Schreckenfuchs, Thomas Digges, Nicolaus Neodomus, Michel Eyquem de Montaigne, Valentin Steinmetz, Diego Lopez de Zuñiga or Didacus a Stunica, Giovanni Battista Benedetti, Francesco Patrizio, Bartholomäus Scultetus, John Blagrave, Jonas Petrejus Upsaliensis, Duncan Liddel, Jean-Antoine de Baïf, Bartholomaeus Keckermann, Christoph Rothmann, Joseph Juste Scaliger (the son of Jules Cesar), Paul Wittich, Valentin Otho, Jacob Christmann, Johannes Amos Comenius, William Gilbert, Giordano Bruno, Tycho Brahe, Michael Mastlin, Johannes Kepler, Joseph Gaultier, Nicolas Fabri de Peiresc, Pierre Gassendi, Pierre de Bérulle, Elia Diodati, Matthias Bernegger, Marin Mersenne, René Descartes, Nicolaus Mulerius, etc.

Here is a list of persons who knew Copernicus' theory before 1615 and who were "anti-Copernicans": Paul Eber, Philip Melanchton, Martin Luther, Jean Calvin, Giovanni Maria Tolosani, Jules Cesar Scaliger, Jorgen Christoffersen Dibvardius or Dybbard, Francesco Maurolico, Jean Bodin, Guillaume de Saluste du Bartas, Wilhelm Misocacus, Francesco Barozzi or Barocius, Thomas Blundeville, Johannes Laurentius Gevaliensis, Lambert Danneau, Jacopo Mazzoni, François Viète, George Buchanan, Giulio Cesare LaGalla, Giovanni Antonio Magini, Jean-Baptiste Morin, Christopher Clavius, etc.


Some errors in biographies of Copernicus come from Galileo.

Galileo boldly and erroneously declared that Copernicus was only a theorician and did not make observations or experiments (he expressed the same wrong crticisim against Descartes and others).
He erroneously told that Copernicus explains the absence of phases of Venus either by transparency or self-lumonisity. It was Regiomontanus who supported the idea of the transparency of Venus, and it was al-Bitruji and Christopher Scheiner who said Venus was self-luminous. Copernicus rightly believed Venus was opaque, and he said nothing about the phases of Venus.
Galileo erroneously said Copernicus was a priest, and that the pope saw his book before it was printed.


Some other errors in biographies of Copernicus come from Jan Czynski's Kopernik et ses travaux, Paris, 1847.

After having taken part in the ill-fated Polish insurection of 1830, Jan Czynski took refuge in France. In order to earn some money, he talked and wrote about Copernicus, mainly using his imagination. He inspired at least 3 French scientists, who wrote soon after a few pages about Copernicus: François Arago, in Oeuvres complètes, Paris, 1854, vol. III; Joseph Bertrand in Les fondateurs de l'astronomie moderne, Paris, 1865; and Camille Flammarion, Vie de Copernic, Paris, 1872.


Errata in my book.

Page 46, read "On 11 January 1503, in Padua" instead of "On 11 January 1503, in Bologna"
Page 57 and 331, read "Theophilacti scolastici Simocati epl'e morales: rurales et amatorie interpretatione latina" instead of "Theophilacti scolastici Simocati epl'e mozales: rurales et amatorie interpzetatione latina".
Pages 125 and 348, read "René Pintard" instead of "Roger Pintard".
Page 279, line 20 should have no italics.
Page 296, line 22 should have no italics.
Page 318, line 24, read "an hypertrophy" instead of "a cancer".
Page 327, read "To the famous man Jean Chapelain" instead of "To the famous man Jean Cappel".


Copernicus, Theophilacti scolastici Simocati epl'e morales: rurales et amatorie interpretatione latina, Cracow, 1509.
[Copernicus &] Rheticus, Narratio prima, Danzig, 1540.
[Copernicus &] Rheticus, Narratio prima, Basel, 1541.
Copernicus, De Lateribus et Angulis Triangolorum, tum planorum rectilineorum, tum Sphaericorum, Wittenberg, 1542.
Copernicus, De revolutionibus orbium coelestium, Libri VI, Nuremberg, 1543.
Copernicus, De revolutionibus orbium coelestium, Libri VI, Basel, 1566.
Copernicus, Astronomia instaurata, Amsterdam, 1617 (3rd ed. of De revolutionibus).
The Manucripts of Nicholas Copernicus, Minor Works. Facsimiles, edited by Pawel Czartoryski, The Polish Academy of Sciences, Warsaw-Cracow, 1985.
The Manucripts of Nicholas Copernicus, On the Revolutions. Facsimiles, edited by Pawel Czartoryski, The Polish Academy of Sciences, Warsaw-Cracow, 1972.
Nicholas Copernicus. Complete works, Minor Works, translated and annotated by Edward Rosen, Polish Scientific Publisher, 1985; reprint, The John Hopkins University Press, 1992.
Nicholas Copernicus. Complete works, On the Revolutions, translated and annotated by Edward Rosen, Polish Scientifc Publisher, 1985; reprint, The John Hopkins University Press, 1992.
Leopold Prowe, Nicolaus Coppernicus, Berlin, 1883-84; reprint, Osnabrück, 1967.
Marian Biskup, Regesta Copernicana (Calendar of Copernicus' papers), Polish Academy of Science Press, 1973.
Owen Gingerich, The Great Copernicus Chase and Other Adventures in Astronomical History, Cambridge, 1992.
Owen Gingerich, The eye of Heaven, Ptolemy Copernicus Kepler, New York, 1993.
Jürgen Hamel, Nicolaus Copernicus, Leben, Werk und Wirkung, Spektrum Akademischer Verlag, 1994.
Edaward Rosen & Erna Hilfstein, Copernicus and his Successors, The Hambledon Press, London, 1995.
Pierre Gassendi & Olivier Thill, The Life of Copernicus, Xulon Press, Fairfax, 2002.

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