Editing Nicolas Léonard Sadi Carnot (section)

==Life==

=== Family background ===
[[File:Lazare Nicolas Marguerite, comte Carnot, général (1753-1823).jpg|thumb|Portrait of Sadi's father, Lazare Carnot (1753–1823) as a [[Napoleon]]ic general, by an unknown artist, ''ca''. 1815, [[Musée de l'Histoire de France (Versailles)|Museum of French History]], Versailles]]

Sadi Carnot was born in [[Paris]] on the 1st of June 1796, at the [[Petit Luxembourg]] palace, where his father [[Lazare Carnot|Lazare]] resided as one of the five members of the [[French Directory|Directory]], the highest governing body of the [[French First Republic]] in the immediate aftermath of the [[Thermidorian Reaction]].  His mother, Sophie ''née'' Dupont (1764-1813), came from a wealthy family based in [[Saint-Omer]].

Sadi was named by his father Lazare after the 13th-century Persian poet [[Saadi Shirazi|Sadi of Shiraz]].  An older brother, also named Sadi, had been born in 1794 but died in infancy the following year.  "Sadi" is the only given name that appears in the second-born's civil birth certificate, dated 14 [[prairial]], year IV in the [[French Republican calendar]].<ref>{{Harvnb|Birembaut|1974|p=362}}</ref>  On 11 July 1796 the child was baptized in the Catholic church of [[Saint-Louis-d'Antin]] as "Nicolas-Léonard Dupont".  The principal witness at that baptism was his maternal grandfather, Jacques-Antoine-Léonard Dupont.  The father is wrongly identified in the baptismal record as Jacques-Léonard-Joseph-Auguste Dupont (who was, in fact, the child's maternal uncle).<ref>{{Harvnb|Birembaut|1974|pp=365–366}}</ref>  Following the biographical notice published long after his death by his brother Hippolyte, most sources now give his full name as "Nicolas Léonard Sadi", but there is no evidence that he ever used any name other than "Sadi".<ref>{{Harvnb|Birembaut|1974|p=362}}</ref>

Sadi had a younger brother, [[Hippolyte Carnot]], who was born in 1801 in Saint-Omer and who would later become a prominent politician.  Hippolyte's eldest son [[Marie François Sadi Carnot]] served as [[President of France]] from 1887 to 1894.  Another of Hippolyte's sons was the chemist, mining engineer and politician [[Adolphe Carnot]].  Sadi himself would remain a bachelor and left no descendants.

=== Education and military career ===
[[File:Felie Carnot 1806.jpg|thumb|Portrait of Sadi Carnot, aged 10, by Félie Carnot, 1806. Académie François Bourdon, [[Le Creusot]], France]]

The young Sadi was educated first at home by his father and later at the [[Lycée Charlemagne]], in Paris, where he prepared for the examinations required to enter the [[École polytechnique]], which his father had helped to establish.  In 1811, at the age of 16 (the minimum allowed) Sadi Carnot became a cadet of the École polytechnique, where his classmates included the future mathematician [[Michel Chasles]].  Among his professors were [[André-Marie Ampère]], [[Siméon Denis Poisson]], [[François Arago]], and [[Gaspard-Gustave Coriolis]].  Thus, the school had become renowned for its instruction in mathematics and physics.<ref>{{Harvnb|O'Connor|Robertson|1998}}</ref>

During the [[Battle of Paris (1814)|Battle of Paris]] in March 1814, Carnot, Chasles, and other cadets of the École polytechnique participated in the defense of [[Vincennes]].  This appears to have been Carnot's only experience of battle.  Carnot graduated in 1814 and was admitted at the [[School of Applied Artillery|École d'application de l'artillerie et du génie]] ("School of Applied Artillery and Military Engineering") in [[Metz]], where he completed a two-year course. Sadi then became an officer in the [[French army]]'s corps of engineers.

Carnot's father Lazare served as [[Napoleon]]'s minister of the interior during the "[[Hundred Days]]", and, after [[Battle of Waterloo|Napoleon's final defeat]] in 1815, Lazare was forced into exile in the German city of [[Magdeburg]]. Sadi's position in the army, under the [[Bourbon Restoration in France|restored Bourbon monarchy]] of King [[Louis XVIII of France|Louis XVIII]], became increasingly difficult.<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|pp=4–5}}</ref>   Lazare never returned to France, dying in Magdeburg in 1823.

Sadi became a [[Captain (armed forces)|captain]] in the ''Génie'' and was posted to various locations, where he inspected [[fortification]]s, tracked plans, and wrote many reports. However, it appeared that his recommendations were ignored and that his career was stagnating.<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|pp=4–5}}</ref>  On 15 September 1818, at the age of 22, he took a six-month leave to prepare for the entrance examination to the newly formed [[Staff (military)|General Staff]] in Paris.  Carnot passed the exam and joined the General Staff in January of 1819, with the lower rank of [[lieutenant]].<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|pp=4–5}}</ref>  He remained on call for military duty, but from then on he dedicated most of his attention to private intellectual pursuits and received only two-thirds pay.<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|pp=4–5}}</ref>

=== Private studies and research ===
In Paris, Carnot befriended [[Nicolas Clément]] and [[Charles-Bernard Desormes]] and attended lectures on physics and chemistry at the [[Sorbonne University|Sorbonne]] and the [[Collège de France]]. He also attended the [[Conservatoire national des arts et métiers]], where he followed the lectures on chemistry by Clément and those on economics by [[Jean-Baptiste Say]].<ref>{{Harvnb|Fox|2012|p=425}}</ref>  Carnot became interested in understanding the limits to improving the performance of [[steam engine]]s, which led him to the investigations that became his ''Reflections on the Motive Power of Fire'', published at his own expense in June 1824.

Carnot was finally promoted to his former rank of captain in September of 1827, but the following April he quit the army, having completed only fifteen months of active service and without right to a pension.<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|p=5}}</ref>  In a directory of alumni of the École polytechnique published by Ambroise Fourcy in 1828, Carnot is listed as "maker of steam engines".  This and some other indications suggest that Carnot may have been involved in a practical scheme for the improvement of steam engines, but no patents or other concrete evidences of that work have emerged.<ref>{{Harvnb|Almanza|Horsin Molinaro|Lo Bue|2024|p=6}}</ref>

=== Views and character ===
[[File:Carnot Despoix 1830.jpg|thumb|right|185px|Drawing of Sadi Carnot by artist Despoix, Paris, 1830.  The original is now in the [[French Academy of Sciences]], Paris.]]

Carnot was interested in [[political economy]].  His political orientation was [[Liberalism|liberal]], but he seems to have preferred the more interventionist doctrines of [[Jean de Sismondi]] to the ''[[laissez-faire]]'' policies advocated by [[classical liberalism|classical liberal]] economists like Say and [[David Ricardo]].<ref>{{Harvnb|Fox|2012|p=418}}</ref>  Out of Carnot's private writings on economics only some fragmentary notes survive.<ref>{{Harvnb|Fox|2012|pp=426–427}}</ref>

Carnot initially welcomed the [[July Revolution]] of 1830, which ended the Bourbonic regime under [[Charles X of France|Charles X]] and established a new [[constitutional monarchy]] under "Citizen King" [[Louis Philippe I|Louis Philippe]].<ref>{{Harvnb|Carnot|1890|pp=32}}</ref>  According to his brother Hippolyte, there was some discussion among leaders of the new regime of incorporating Sadi to the [[Chamber of Peers (France)|Chamber of Peers]], as he could be considered to have inherited the [[Nobility of the First French Empire|Imperial title]] of "Count Carnot" that Napoleon had bestowed on his father Lazare in 1815.  Nothing came of this, however, perhaps because Sadi's [[Republicanism|republican]] convictions prevented him from accepting a hereditary distinction.<ref>{{Harvnb|Wilson|1981|p=145}}</ref>

According to recollections published long after Sadi's death by his brother Hippolyte, Sadi was an avid reader of [[Blaise Pascal]], [[Molière]] and [[Jean de La Fontaine]].<ref>{{Harvnb|Carnot|1890|p=28}}</ref>  Hippolyte recalled that Sadi was a [[Philosophical theism|philosophical theist]] who believed in divine causality but not in divine punishment.  Carnot wrote in his private papers that "what to an ignorant man is chance, cannot be chance to one better instructed".  He was critical of established religion, but spoke in favor of "the belief in an all-powerful Being, who loves us and watches over us."<ref>{{Harvnb|Carnot|1890|pp=215–217}}</ref>

Hippolyte also described his brother as a talented [[violin]] player, interested principally in the music of [[Jean-Baptiste Lully]] and [[Giovanni Battista Viotti]], who also cultivated gymnastics, fencing, swimming, dancing, and skating.<ref>{{Harvnb|Carnot|1890|pp=28–29}}</ref>  According to historian of science James F. Challey, "although sensitive and perceptive", Carnot "appeared extremely introverted, even aloof, to all but a few close friends."<ref>{{Harvnb|Challey|1981|p=80}}</ref>  This may help explain why Carnot's work failed to make any significant impression within either the scientific or the engineering community during his lifetime.

=== Illness and death ===

In the summer of 1832 Carnot apparently suffered from a severe bout of [[scarlet fever]].  On 3 August he was interned in a private sanatorium run by psychiatrist [[Jean-Étienne Dominique Esquirol|Jean-Étienne Esquirol]] and located in [[Ivry-sur-Seine|Ivry]], just south of Paris.<ref>{{Harvnb|Birembaut|1974|pp=356,369–370}}</ref>  According to the hospital record, he was cured from "[[mania]]" but then died of [[cholera]] on 24 August.<ref>{{Harvnb|Birembaut|1974|p=370}}</ref>  Carnot was buried in the old cemetery of Ivry, close to what is now the [[Mairie d'Ivry station]].<ref>{{Harvnb|Birembaut|1974|p=363}}</ref>