Jean Paul de Gua de Malves (1713,

Malves-en-Minervois Malves-en-Minervois is a Communes of France, commune in the Aude Departments of France, department in southern France. Population See also *Communes of the Aude department References

Communes of Aude Aude communes articles need ...

(Aude) – June 2, 1785, ParisOpen Site - Science: Mathematics: Mathematicians: Gua de Malves, Jean
/ref>) 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, structure, space, models, and change. History On ...

who published in 1740 a work on

analytical geometry In classical mathematics, analytic geometry, also known as coordinate geometry or Cartesian geometry, is the study of geometry using a coordinate system. This contrasts with synthetic geometry. Analytic geometry is used in physics and engineerin ...

in which he applied it, without the aid of

differential calculus In mathematics, differential calculus is a subfield of calculus that studies the rates at which quantities change. It is one of the two traditional divisions of calculus, the other being integral calculus—the study of the area beneath a curve. ...

, to find the

tangent In geometry, the tangent line (or simply tangent) to a plane curve at a given point is the straight line that "just touches" the curve at that point. Leibniz defined it as the line through a pair of infinitely close points on the curve. More ...

asymptote In analytic geometry, an asymptote () of a curve is a line such that the distance between the curve and the line approaches zero as one or both of the ''x'' or ''y'' coordinates tends to infinity. In projective geometry and related contexts, ...

s, and various singular points of an

algebraic curve In mathematics, an affine algebraic plane curve is the zero set of a polynomial in two variables. A projective algebraic plane curve is the zero set in a projective plane of a homogeneous polynomial in three variables. An affine algebraic plane c ...

Gua de Malves - Usages de l'analyse de Descartes, 1740 - BEIC 1460763

He further showed how singular points and isolated loops were affected by

conical projection In cartography, map projection is the term used to describe a broad set of transformations employed to represent the two-dimensional curved surface of a globe on a plane. In a map projection, coordinates, often expressed as latitude and longitu ...

. He gave the proof of Descartes's rule of signs which is to be found in most modern works. It is not clear whether Descartes ever proved it strictly, and

Newton Newton most commonly refers to: * Isaac Newton (1642–1726/1727), English scientist * Newton (unit), SI unit of force named after Isaac Newton Newton may also refer to: Arts and entertainment * ''Newton'' (film), a 2017 Indian film * Newton ( ...

seems to have regarded it as obvious. De Gua de Malves was acquainted with many of the French philosophes during the last decades of the

Ancien Régime ''Ancien'' may refer to * the French word for "ancient, old" ** Société des anciens textes français * the French for "former, senior" ** Virelai ancien ** Ancien Régime ** Ancien Régime in France {{disambig ...

. He was an early, short-lived, participant, then editor (later replaced by Diderot) of the project that ended up as the ''

Encyclopédie ''Encyclopédie, ou dictionnaire raisonné des sciences, des arts et des métiers'' (English: ''Encyclopedia, or a Systematic Dictionary of the Sciences, Arts, and Crafts''), better known as ''Encyclopédie'', was a general encyclopedia publis ...

''.

Condorcet Marie Jean Antoine Nicolas de Caritat, Marquis of Condorcet (; 17 September 1743 – 29 March 1794), known as Nicolas de Condorcet, was a French philosopher and mathematician. His ideas, including support for a liberal economy, free and equal pu ...

claimed that it was in fact the de Gua who recruited

Diderot Denis Diderot (; ; 5 October 171331 July 1784) was a French philosopher, art critic, and writer, best known for serving as co-founder, chief editor, and contributor to the ''Encyclopédie'' along with Jean le Rond d'Alembert. He was a prominen ...

to the project, though this claim has never been verified. In either case, Jean-Paul and

Jean le Rond d'Alembert Jean-Baptiste le Rond d'Alembert (; ; 16 November 1717 – 29 October 1783) was a French mathematician, mechanician, physicist, philosopher, and music theorist. Until 1759 he was, together with Denis Diderot, a co-editor of the ''Encyclopédie ...

, also thought to have been recruited by the de Gua, first show up on the December 1746 payroll of the publishers who were backing the Encyclopédie project. Diderot was added just weeks later and took over as editor on 16 October 1747. At the funeral of the "profound geometrician", as Diderot called him, the eulogy was given by Condorcet. He was elected a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, incl ...

in 1743.

References

Bibliography

*Arthur M. Wilson: ''Diderot''. Oxford University Press, New York, 1972, pp. 79–81. *

Nicolas de Condorcet Marie Jean Antoine Nicolas de Caritat, Marquis of Condorcet (; 17 September 1743 – 29 March 1794), known as Nicolas de Condorcet, was a French philosopher and mathematician. His ideas, including support for a liberal economy, free and equal pu ...

, « Éloge de M. l’abbé de Gua », ''Œuvres de Condorcet'', Firmin Didot frères, 1847-1849, Paris, p. 241-58.
online copy
*Rene Taton

Complete Dictionary of Scientific Biography, 2008. * {{DEFAULTSORT:Gua de Malves, Jean Paul de 1713 births 1785 deaths People from Carcassonne English–French translators 18th-century French mathematicians Members of the French Academy of Sciences Contributors to the Encyclopédie (1751–1772) Fellows of the Royal Society French geometers 18th-century French translators