Marin Mersenne,
OM (also known as Marinus Mersennus or ''le Père'' Mersenne; ; 8 September 1588 – 1 September 1648) was a French
polymath
A polymath ( el, πολυμαθής, , "having learned much"; la, homo universalis, "universal human") is an individual whose knowledge spans a substantial number of subjects, known to draw on complex bodies of knowledge to solve specific pro ...
whose works touched a wide variety of fields. He is perhaps best known today among mathematicians for
Mersenne prime
In mathematics, a Mersenne prime is a prime number that is one less than a power of two. That is, it is a prime number of the form for some integer . They are named after Marin Mersenne, a French Minim friar, who studied them in the early 17 ...
numbers, those which can be written in the form for some
integer
An integer is the number zero (), a positive natural number (, , , etc.) or a negative integer with a minus sign ( −1, −2, −3, etc.). The negative numbers are the additive inverses of the corresponding positive numbers. In the languag ...
. He also developed
Mersenne's laws, which describe the harmonics of a vibrating string (such as may be found on
guitar
The guitar is a fretted musical instrument that typically has six strings. It is usually held flat against the player's body and played by strumming or plucking the strings with the dominant hand, while simultaneously pressing selected string ...
s and
piano
The piano is a stringed keyboard instrument in which the strings are struck by wooden hammers that are coated with a softer material (modern hammers are covered with dense wool felt; some early pianos used leather). It is played using a keyboa ...
s), and his seminal work on
music theory, ''
Harmonie universelle'', for which he is referred to as the "father of
acoustics". Mersenne, an ordained
Catholic priest
The priesthood is the office of the ministers of religion, who have been commissioned (" ordained") with the Holy orders of the Catholic Church. Technically, bishops are a priestly order as well; however, in layman's terms ''priest'' refers onl ...
, had many contacts in the scientific world and has been called "the center of the world of science and mathematics during the first half of the 1600s"
and, because of his ability to make connections between people and ideas, "the post-box of Europe". He was also a member of the
Minim religious order and wrote and lectured on
theology
Theology is the systematic study of the nature of the divine and, more broadly, of religious belief. It is taught as an academic discipline, typically in universities and seminaries. It occupies itself with the unique content of analyzing th ...
and
philosophy
Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. ...
.
Life
Mersenne was born of Jeanne Moulière, wife of Julien Mersenne, peasants who lived near
Oizé,
County of Maine (present-day
Sarthe, France). He was educated at
Le Mans
Le Mans (, ) is a city in northwestern France on the Sarthe River where it meets the Huisne. Traditionally the capital of the province of Maine, it is now the capital of the Sarthe department and the seat of the Roman Catholic diocese of Le ...
and at the
Jesuit College of La Flèche. On 17 July 1611, he joined the
Minim Friars and, after studying theology and
Hebrew
Hebrew (; ; ) is a Northwest Semitic language of the Afroasiatic language family. Historically, it is one of the spoken languages of the Israelites and their longest-surviving descendants, the Jews and Samaritans. It was largely preserved ...
in Paris, was ordained a priest in 1613.
Between 1614 and 1618, he taught theology and philosophy at
Nevers
Nevers ( , ; la, Noviodunum, later ''Nevirnum'' and ''Nebirnum'') is the prefecture of the Nièvre Departments of France, department in the Bourgogne-Franche-Comté Regions of France, region in central France. It was the principal city of the ...
, but he returned to Paris and settled at the convent of
L'Annonciade in 1620. There he studied mathematics and music and met with other kindred spirits such as
René Descartes
René Descartes ( or ; ; Latinized: Renatus Cartesius; 31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician, widely considered a seminal figure in the emergence of modern philosophy and science. Ma ...
,
Étienne Pascal,
Pierre Petit Pierre Petit may refer to:
* Pierre Petit (engineer) (1594–1677), French military engineer, mathematician, and physicist
* Pierre Petit (scholar) (1617–1687), French poet, doctor, and classicist
* Pierre Petit (photographer) (1832–1909), Fr ...
,
Gilles de Roberval,
Thomas Hobbes
Thomas Hobbes ( ; 5/15 April 1588 – 4/14 December 1679) was an English philosopher, considered to be one of the founders of modern political philosophy. Hobbes is best known for his 1651 book '' Leviathan'', in which he expounds an influ ...
, and
Nicolas-Claude Fabri de Peiresc
Nicolas-Claude Fabri de Peiresc (1 December 1580 – 24 June 1637), often known simply as Peiresc, or by the Latin form of his name, Peirescius, was a French astronomer, antiquary and savant, who maintained a wide correspondence with scientis ...
. He corresponded with
Giovanni Doni,
Jacques Alexandre Le Tenneur,
Constantijn Huygens,
Galileo Galilei
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He ...
, and other scholars in Italy, England and the
Dutch Republic
The United Provinces of the Netherlands, also known as the (Seven) United Provinces, officially as the Republic of the Seven United Netherlands ( Dutch: ''Republiek der Zeven Verenigde Nederlanden''), and commonly referred to in historiograph ...
. He was a staunch defender of Galileo, assisting him in translations of some of his mechanical works.
For four years, Mersenne devoted himself entirely to philosophic and theological writing, and published ''Quaestiones celeberrimae in Genesim'' (''Celebrated Questions on the Book of Genesis'') (1623); ''L'Impieté des déistes'' (''The Impiety of the
Deists'') (1624); ''La Vérité des sciences'' (''Truth of the Sciences Against the Sceptics'', 1624). It is sometimes incorrectly stated that he was a
Jesuit. He was educated by Jesuits, but he never joined the
Society of Jesus
, image = Ihs-logo.svg
, image_size = 175px
, caption = ChristogramOfficial seal of the Jesuits
, abbreviation = SJ
, nickname = Jesuits
, formation =
, founders ...
. He taught theology and philosophy at Nevers and Paris.
In 1635 he set up the informal ''Académie Parisienne'' (Academia Parisiensis), which had nearly 140 correspondents, including astronomers and philosophers as well as mathematicians, and was the precursor of the
Académie des sciences
The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at ...
established by
Jean-Baptiste Colbert in 1666. He was not afraid to cause disputes among his learned friends in order to compare their views, notable among which were disputes between Descartes and
Pierre de Fermat
Pierre de Fermat (; between 31 October and 6 December 1607 – 12 January 1665) was a French mathematician who is given credit for early developments that led to infinitesimal calculus, including his technique of adequality. In particular, he ...
and
Jean de Beaugrand.
Peter L. Bernstein
Peter Lewyn Bernstein (January 22, 1919 – June 5, 2009) was an American financial historian, economist and educator whose development and refinement of the efficient-market hypothesis made him one of the country's best known authorities in ...
, in his book ''Against the Gods: The Remarkable Story of Risk'', wrote, "The Académie des Sciences in Paris and the Royal Society in London, which were founded about twenty years after Mersenne's death, were direct descendants of Mersenne's activities."
In 1635 Mersenne met with
Tommaso Campanella but concluded that he could "teach nothing in the sciences ... but still he has a good memory and a fertile imagination." Mersenne asked if Descartes wanted Campanella to come to Holland to meet him, but Descartes declined. He visited Italy fifteen times, in 1640, 1641 and 1645. In 1643–1644 Mersenne also corresponded with the German Socinian
Marcin Ruar Marcin (Polish pronunciation: ) is a male given name or surname.
Notable people with the name Marcin include:
Given name
* Marcin Dorociński (born 1973), Polish actor
* Marcin Gortat (born 1984), Polish basketball player
* Marcin Held (born 1992 ...
concerning the Copernican ideas of
Pierre Gassendi
Pierre Gassendi (; also Pierre Gassend, Petrus Gassendi; 22 January 1592 – 24 October 1655) was a French philosopher, Catholic priest, astronomer, and mathematician. While he held a church position in south-east France, he also spent much t ...
, finding Ruar already a supporter of Gassendi's position. Among his correspondents were Descartes, Galileo, Roberval,
Pascal
Pascal, Pascal's or PASCAL may refer to:
People and fictional characters
* Pascal (given name), including a list of people with the name
* Pascal (surname), including a list of people and fictional characters with the name
** Blaise Pascal, Frenc ...
,
Beeckman and other scientists.
He died on 1 September 1648 of complications arising from a
lung abscess
Lung abscess is a type of liquefactive necrosis of the lung tissue and formation of cavities (more than 2 cm) containing necrotic debris or fluid caused by microbial infection.
This pus-filled cavity is often caused by aspiration, which may ...
.
Work
''Quaestiones celeberrimae in Genesim'' was written as a commentary on the
Book of Genesis
The Book of Genesis (from Greek ; Hebrew: בְּרֵאשִׁית ''Bəreʾšīt'', "In hebeginning") is the first book of the Hebrew Bible and the Christian Old Testament. Its Hebrew name is the same as its first word, ( "In the beginning" ...
and comprises uneven sections headed by verses from the first three chapters of that book. At first sight the book appears to be a collection of treatises on various miscellaneous topics. However Robert Lenoble has shown that the principle of unity in the work is a polemic against
magical and
divinatory
Divination (from Latin ''divinare'', 'to foresee, to foretell, to predict, to prophesy') is the attempt to gain insight into a question or situation by way of an occultic, standardized process or ritual. Used in various forms throughout history ...
arts,
cabalism, and
animistic
Animism (from Latin: ' meaning 'breath, spirit, life') is the belief that objects, places, and creatures all possess a distinct spiritual essence. Potentially, animism perceives all things—animals, plants, rocks, rivers, weather systems, h ...
and
pantheistic philosophies. He mentions
Martin Del Rio's ''Investigations into Magic'' and criticises
Marsilio Ficino for claiming power for images and characters. He condemns astral magic and
astrology
Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that claim to discern information about human affairs and terrestrial events by studying the apparent positions of celestial objects. Di ...
and the ''
anima mundi'', a concept popular amongst
Renaissance
The Renaissance ( , ) , from , with the same meanings. is a period in European history marking the transition from the Middle Ages to modernity and covering the 15th and 16th centuries, characterized by an effort to revive and surpass ide ...
neo-platonists. Whilst allowing for a mystical interpretation of the Cabala, he wholeheartedly condemned its magical application, particularly
angelology. He also criticises
Pico della Mirandola
Giovanni Pico della Mirandola (24 February 1463 – 17 November 1494) was an Italian Renaissance nobleman and philosopher. He is famed for the events of 1486, when, at the age of 23, he proposed to defend 900 theses on religion, philosophy, ...
,
Cornelius Agrippa,
Francesco Giorgio
Francesco Giorgi Veneto (1466–1540) was an Italian Franciscan friar, and author of the work ''De harmonia mundi totius'' from 1525. In it Giorgio proposed an idea of the Universe created according to the universal system of proportion, which m ...
and
Robert Fludd
Robert Fludd, also known as Robertus de Fluctibus (17 January 1574 – 8 September 1637), was a prominent English Paracelsian physician with both scientific and occult interests. He is remembered as an astrologer, mathematician, cosmologis ...
, his main target. Fludd responded with ''Sophia cum moria certamen'' (1626), wherein he discusses his involvement with the
Rosicrucians. The anonymous ''Summum bonum'' (1629), another critique of Mersenne, is a Rosicrucian-themed text. The cabalist
Jacques Gaffarel joined Fludd's side, while
Pierre Gassendi
Pierre Gassendi (; also Pierre Gassend, Petrus Gassendi; 22 January 1592 – 24 October 1655) was a French philosopher, Catholic priest, astronomer, and mathematician. While he held a church position in south-east France, he also spent much t ...
defended Mersenne.
''Harmonie universelle'' is perhaps Mersenne's most influential work. It is one of the earliest comprehensive works on music theory, touching on a wide range of musical concepts, and especially the mathematical relationships involved in music. The work contains the earliest formulation of what has become known as
Mersenne's laws, which describe the frequency of oscillation of a stretched string. This frequency is:
# Inversely proportional to the length of the string (this was known to the ancients; it is usually credited to
Pythagoras
Pythagoras of Samos ( grc, Πυθαγόρας ὁ Σάμιος, Pythagóras ho Sámios, Pythagoras the Samian, or simply ; in Ionian Greek; ) was an ancient Ionian Greek philosopher and the eponymous founder of Pythagoreanism. His poli ...
)
# Proportional to the square root of the stretching force, and
# Inversely proportional to the square root of the mass per unit length.
The formula for the lowest frequency is
:
where ''f'' is the frequency
z ''L'' is the length
''F'' is the force
and μ is the mass per unit length
g/m
In this book, Mersenne also introduced several innovative concepts that can be considered the basis of modern reflecting telescopes:
* Much earlier than
Laurent Cassegrain
Laurent Cassegrain (; – 1 September 1693) was a Catholic priest who is notable as the probable inventor of the Cassegrain reflector, a folded two-mirror reflecting telescope design.
Biography
Laurent Cassegrain was born in the region of Chartr ...
, he found the fundamental arrangement of the two-mirror telescope combination, a concave primary mirror associated with a convex secondary mirror, and discovered the telephoto effect that is critical in reflecting telescopes, although he was far from having understood all the implications of that discovery.
* Mersenne invented the
afocal telescope and the beam compressor that is useful in many multiple-mirror telescope designs.
* He recognized also that he could correct the
spherical aberration of the telescope by using aspherical mirrors and that in the particular case of the afocal arrangement he could do this correction by using two parabolic mirrors, though a
hyperboloid is required.
Because of criticism that he encountered, especially from Descartes, Mersenne made no attempt to build a telescope of his own.
Mersenne is also remembered today thanks to his association with the
Mersenne prime
In mathematics, a Mersenne prime is a prime number that is one less than a power of two. That is, it is a prime number of the form for some integer . They are named after Marin Mersenne, a French Minim friar, who studied them in the early 17 ...
s. The
Mersenne Twister, named for Mersenne primes, is frequently used in computer engineering and in related fields such as cryptography.
However, Mersenne was not primarily a mathematician; he wrote about
music theory and other subjects. He edited works of
Euclid
Euclid (; grc-gre, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of ...
,
Apollonius,
Archimedes, and other
Greek mathematicians
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
* Greeks, an ethnic group.
* Greek language, a branch of the Indo-European language family.
** Proto-Greek language, the assumed last common ances ...
. But perhaps his most important contribution to the advance of learning was his extensive correspondence (in
Latin
Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...
) with mathematicians and other scientists in many countries. At a time when the
scientific journal had not yet come into being, Mersenne was the centre of a network for exchange of information.
It has been argued that Mersenne used his lack of mathematical specialty, his ties to the print world, his legal acumen, and his friendship with the French mathematician and philosopher René Descartes (1596–1650) to manifest his international network of mathematicians.
Mersenne's philosophical works are characterized by wide scholarship and the narrowest theological orthodoxy. His greatest service to philosophy was his enthusiastic defence of Descartes, whose agent he was in Paris and whom he visited in exile in the
Netherlands
)
, anthem = ( en, "William of Nassau")
, image_map =
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of the Netherlands
, established_title = Before independence
, established_date = Spanish Netherl ...
. He submitted to various eminent Parisian thinkers a manuscript copy of the ''
Meditations on First Philosophy'', and defended its orthodoxy against numerous clerical critics.
In later life, he gave up speculative thought and turned to scientific research, especially in mathematics, physics and astronomy. In this connection, his best known work is ''
Harmonie universelle'' of 1636, dealing with the
theory of music and
musical instrument
A musical instrument is a device created or adapted to make musical sounds. In principle, any object that produces sound can be considered a musical instrument—it is through purpose that the object becomes a musical instrument. A person who pl ...
s. It is regarded as a source of information on 17th-century music, especially French music and musicians, to rival even the works of
Pietro Cerone.
One of his many contributions to
musical tuning theory was the suggestion of
: