Joseph Diez Gergonne (19 June 1771 at
Nancy,
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
– 4 May 1859 at
Montpellier
Montpellier (; ) is a city in southern France near the Mediterranean Sea. One of the largest urban centres in the region of Occitania (administrative region), Occitania, Montpellier is the prefecture of the Departments of France, department of ...
, France) was a French
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...
and
logician.
Life
In 1791, Gergonne enlisted in the French army as a captain. That army was undergoing rapid expansion because the French government feared a foreign invasion intended to undo the
French Revolution and restore
Louis XVI
Louis XVI (Louis-Auguste; ; 23 August 1754 – 21 January 1793) was the last king of France before the fall of the monarchy during the French Revolution. The son of Louis, Dauphin of France (1729–1765), Louis, Dauphin of France (son and heir- ...
to the throne of France. He saw action in the major
battle of Valmy on 20 September 1792. He then returned to civilian life but soon was called up again and took part in the French invasion of Spain in 1794.
In 1795, Gergonne and his regiment were sent to
Nîmes
Nîmes ( , ; ; Latin: ''Nemausus'') is the Prefectures in France, prefecture of the Gard Departments of France, department in the Occitania (administrative region), Occitanie Regions of France, region of Southern France. Located between the Med ...
. At this point, he made a definitive transition to civilian life by taking up the chair of "transcendental mathematics" at the new École centrale. He came under the influence of
Gaspard Monge
Gaspard Monge, Comte de Péluse (; 9 May 1746 – 28 July 1818) was a French mathematician, commonly presented as the inventor of descriptive geometry, (the mathematical basis of) technical drawing, and the father of differential geometry. Dur ...
, the Director of the new
École polytechnique
(, ; also known as Polytechnique or l'X ) is a ''grande école'' located in Palaiseau, France. It specializes in science and engineering and is a founding member of the Polytechnic Institute of Paris.
The school was founded in 1794 by mat ...
in
Paris
Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...
.
In 1810, in response to difficulties he encountered in trying to publish his work, Gergonne founded his own mathematics journal, officially named the ''
Annales de mathématiques pures et appliquées'' but generally referred to as the ''
Annales de Gergonne''. The most common subject of articles in his journal was
geometry
Geometry (; ) is a branch of mathematics concerned with properties of space such as the distance, shape, size, and relative position of figures. Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician w ...
, Gergonne's specialty. Over a period of 22 years, the ''Annales de Gergonne'' published about 200 articles by Gergonne himself, and other articles by many distinguished mathematicians, including
Poncelet,
Servois,
Bobillier,
Steiner,
Plücker,
Chasles,
Brianchon,
Dupin,
Lamé, even
Galois.
Gergonne was appointed to the chair of astronomy at the University of Montpellier in 1816. In 1830, he was appointed
Rector of the University of Montpellier, at which time he ceased publishing his journal. He retired in 1844.
Work
Gergonne was among the first mathematicians to employ the word
''polar''. In a series of papers beginning in 1810, he contributed to elaborating the
principle of duality in
projective geometry
In mathematics, projective geometry is the study of geometric properties that are invariant with respect to projective transformations. This means that, compared to elementary Euclidean geometry, projective geometry has a different setting (''p ...
, by noticing that every
theorem
In mathematics and formal logic, a theorem is a statement (logic), statement that has been Mathematical proof, proven, or can be proven. The ''proof'' of a theorem is a logical argument that uses the inference rules of a deductive system to esta ...
in the
plane connecting points and lines corresponds to another theorem in which points and lines are interchanged, provided that the theorem embodied no metrical notions. Gergonne was an early proponent of the techniques of
analytical geometry and in 1814, he devised an elegant coordinate solution to the classical
problem of Apollonius: to find a circle which touches three given circles, thus demonstrating the power of the new methods.
In 1813, Gergonne wrote the prize-winning essay for the Bordeaux Academy, ''Methods of synthesis and analysis in mathematics'', unpublished to this day and known only via a summary. The essay is very revealing of Gergonne's philosophical ideas. He called for the abandonment of the words ''
analysis
Analysis (: analyses) is the process of breaking a complex topic or substance into smaller parts in order to gain a better understanding of it. The technique has been applied in the study of mathematics and logic since before Aristotle (38 ...
'' and ''
synthesis'', claiming they lacked clear meanings. Surprisingly for a geometer, he suggested that algebra is more important than geometry at a time when
algebra
Algebra is a branch of mathematics that deals with abstract systems, known as algebraic structures, and the manipulation of expressions within those systems. It is a generalization of arithmetic that introduces variables and algebraic ope ...
consisted almost entirely of the elementary algebra of the
real field. He predicted that one day quasi-mechanical methods would be used to discover new results.
In 1815, Gergonne wrote the first paper on the
optimal design of
experiments
An experiment is a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried. Experiments provide insight into Causality, cause-and-effect by demonstrating what outcome o ...
for
polynomial regression. According to
S. M. Stigler, Gergonne is the pioneer of
optimal design as well as
response surface methodology.
He published his "Essai sur la théorie des définitions" (An essay on the theory of definition) in his ''Annales'' in 1818. This essay is generally credited for first recognizing and naming the construct of ''implicit definition''.
Quote
*"It is not possible to feel satisfied at having said the last word about some theory as long as it cannot be explained in a few words to any passer-by encountered in the street."
[ Michel Chasles]
Aperçu historique
Volume 2. 1875.
Notes
References
*
*
External links
*Biography in the MacTutor History of Mathematics archive
{{DEFAULTSORT:Gergonne, Joseph Diaz
1771 births
1859 deaths
18th-century French mathematicians
19th-century French mathematicians
French logicians
French geometers
French military personnel of the French Revolutionary Wars
Scientists from Nancy, France
18th-century French philosophers
19th-century French philosophers
French male non-fiction writers
19th-century French male writers
18th-century French male writers