Claude Bernard

{{For|the 17th-century Roman Catholic priest who popularized the Memorare|Father Claude Bernard}}

{{Infobox scientist

| image = Claude Bernard.jpg

| birth_date = {{Birth date|1813|7|12|df=y}}

| birth_place = Saint-Julien, Rhône, France

| death_date = {{Death date and age|1878|2|10|1813|7|12|df=y}}

| death_place = Paris, France

| spouse = {{marriage|Marie Françoise Martin|1845|1869|end=sep.}}

| children = Two daughters, Jeanne-Henriette and Marie-Claude, {{nowrap|and a son who died in infancy}}

| patrons = Louis Napoleon

| field = Physiology

| work_institutions = Muséum national d'Histoire naturelle

| alma_mater = University of Paris

| known_for = Milieu intérieur (internal environment)

| prizes = Baly Medal (1869)
Copley Medal (1876)

| signature = Claude Bernard signature.svg

}}

Claude Bernard ({{IPA|fr|klod bɛʁnaʁ|lang}}; 12 July 1813 – 10 February 1878) was a French physiologist. I. Bernard Cohen of Harvard University called Bernard "one of the greatest of all men of science".{{cite book|editor-link=I. Bernard Cohen|editor-last=Cohen|editor-first=I. Bernard|chapter=Foreword|publisher=Dover Publications|date=1957|last=Bernard|first=Claude|translator-last=Copley Greene|translator-first=Henry|title=An Introduction to the Study of Experimental Medicine|orig-date=1865|url=https://books.google.com/books?id=MIx8D61JlboC|page=i}} He originated the term milieu intérieur and the associated concept of homeostasis (the latter term being coined by Walter Cannon).{{cite journal | last1 = Gross | first1 = Charles G. | title = Claude Bernard and the constancy of the internal environment | journal = The Neuroscientist | volume = 4 | pages = 380–385 | date = 1 September 1998 | issue = 5 | doi = 10.1177/107385849800400520 | s2cid = 51424670 | url = https://journals.sagepub.com/doi/10.1177/107385849800400520 | access-date = 1 June 2021 | archive-date = 9 February 2023 | archive-url = https://web.archive.org/web/20230209044815/https://journals.sagepub.com/doi/10.1177/107385849800400520 | url-status = live | url-access = subscription }}{{cite journal |title=Homeostasis: The Underappreciated and Far Too Often Ignored Central Organizing Principle of Physiology |journal=Frontiers in Physiology |year=2020 |last=Billman |first=George E.|author-link=George Billman |volume=11 |page=200 |pmc=7076167|doi=10.3389/fphys.2020.00200|pmid=32210840 |doi-access=free }}

Life

Bernard was born in 12 July 1813 in the village of Saint-Julien,{{cite journal|pages=567–578|url=https://books.google.com/books?id=xyQDAAAAMBAJ&pg=PA567|title=Claude Bernard|journal=Popular Science|author1=D. Wright Wilson|publisher=Bonnier Corporation|date=June 1914}} near Villefranche-sur-Saône. He received his early education in the Jesuit school of that town, then attended college at Lyon, which he soon left to become assistant in a druggist's shop. He is sometimes described as an agnostic,{{cite book|title=Doctors and Discoveries: Lives That Created Today's Medicine|url=https://archive.org/details/doctorsdiscoveri00john|url-access=registration|year=2002|publisher=Houghton Mifflin Harcourt|isbn=978-0-618-15276-6|first=John G.|last=Simmons|page=[https://archive.org/details/doctorsdiscoveri00john/page/17 17]|quote=Upon his death on February 10, 1878, Bernard received a state funeral – the first French scientist to be so honored. The procession ended at Pere Lachaise cemetery, and Gustave Flaubert described it later with a touch of irony as 'religious and very beautiful'. Bernard was an agnostic.}} and even humorously referred to by his colleagues as a "great priest of atheism". Despite this, after his death Cardinal Ferdinand Donnet claimed Bernard was a fervent Catholic,{{Cite journal| issn = 0440-8888| volume = 32| issue = 1| pages = 51–55| last = Donnet| first = Vincent| title = Claude Bernard était-il athée? |trans-title=Was Claude Bernard an atheist?| journal = Histoire des Sciences Médicales| date = 1998| pmid = 11625277|url=https://www.biusante.parisdescartes.fr/sfhm/hsm/HSMx1998x032x001/HSMx1998x032x001x0051.pdf|language=fr}} with a biographical entry in the Catholic Encyclopedia.{{Cite web|url=http://www.newadvent.org/cathen/02497a.htm|publisher=Catholic Encyclopedia|title=Claude Bernard|via=newadvent.org}} His leisure hours were devoted to the composition of a vaudeville comedy, and the success it achieved moved him to attempt a prose drama in five acts, Arthur de Bretagne. Arthur de Bretagne,{{cite web | url = https://marduel.com/dossiers/claude-bernard.pdf | title=Claude Bernard, un physiologiste natif du Beaujolais: Sa famille, sa vie, son oeuvre|trans-title=Claude Bernard, a physiologist born in Beaujolais: His family, his life, his work|last=Marduel|first=Marie-Aymée|date=2006|publisher= Marie-Aymée Marduel|language=fr|pages=6, 24 | access-date = 25 April 2021}} was published only after his death.{{cite book| last= Bernard | first = Claude | title = Arthur de Bretagne | publisher = E. Dentu | place = Paris | date = 1887}} A second edition appeared in 1943.{{cite book| last= Bernard | first = Claude | title = Arthur de Bretagne | publisher = J.-M. Le Goff | place = Paris | date = 1943 | edition= 2nd}}

In 1834, at the age of twenty-one, he went to Paris to present this play to critic Saint-Marc Girardin, but was dissuaded from adopting literature as a profession. Girardin urged him to take up the study of medicine instead. Bernard followed his advice, later becoming an interne at the Hôtel-Dieu de Paris. There, he met physiologist François Magendie, who served as physician at the hospital. Bernard became preparateur (lab assistant) at the {{lang|fr|Collège de France|italic=no}} in 1841.

Image:Plaque Claude Bernard laboratoire.jpg

In 1845, he married Marie Françoise "Fanny" Martin for convenience; the marriage was arranged by a colleague and her dowry helped finance his experiments. In 1847 he was appointed Magendie's deputy-professor at the college, and in 1855 he succeeded him as full professor. In 1860, Bernard was elected an international member of the American Philosophical Society.{{Cite web|title=Member History|url=https://search.amphilsoc.org/memhist/search?creator=Claude+Bernard&title=&subject=&subdiv=&mem=&year=&year-max=&dead=&keyword=&smode=advanced|access-date=2021-01-15|publisher=American Philosophical Society}} His field of research was considered inferior at the time, and the laboratory assigned to him was a "regular cellar."{{cite book|page=42|url=https://archive.org/details/lifeofpasteur00vall|title=Life of Pasteur 1928|isbn=9780766143524|last1=Vallery-Radot|first1=René|date=2003-03-01|publisher=Kessinger}}

Bernard was chosen around this time to be the inaugural Chair of physiology at the Sorbonne, but no laboratory was provided for his use. After speaking with Bernard in 1864, Louis Napoleon built a laboratory at the Muséum national d'Histoire naturelle in the Jardin des Plantes for him. At the same time, Napoleon III established a professorship which Bernard accepted, leaving the Sorbonne in 1868. In the same year, he was also admitted a member of the Académie française and elected a foreign member of the Royal Swedish Academy of Sciences.

When he died on 10 February 1878, he was given a public funeral, which France had never allowed for a man of science.{{cite EB1911|wstitle= Bernard, Claude|volume=3|page=798}} He was interred in Père Lachaise Cemetery in Paris.

Career

File:Portrait of Claude Bernard .PNG]]

File:Claude Bernard and pupils Wellcome L0019301.jpg

File:Bernard Claude.jpg

Bernard's first major work was on the functions of the pancreas. His discovery that the juices are a significant part of the digestive process won him the prize for experimental physiology from the French Academy of Sciences.{{cite news|title=Comptes rendus hebdomadaires des séances de l'Académie des sciences|trans-title=Weekly reports of the sessions of the Academy of Sciences|date=1847|issue=24|url=https://gallica.bnf.fr/ark:/12148/bpt6k29812|newspaper=Académie des sciences|location=Paris|language=fr}} In perhaps his most famous experiment, he discovered the glycogenic function of the liver.{{cite journal |first=F. G.|last=Young |title=Claude Bernard and the Discovery of Glycogen|journal=British Medical Journal |volume=1 |issue=5033 |pages=1431–1437 |date=22 June 1957|jstor=25382898 |doi=10.1136/bmj.1.5033.1431|pmid=13436813|pmc=1973429 }} The liver, in addition to secreting bile, also produces the sugars that can cause hypoglycemia, which helped advance study of diabetes mellitus and its causes.{{cite journal|url=https://www.sciencedirect.com/science/article/abs/pii/0165183885901110|title=Hyperglycaemia: Imitating Claude Bernard's Piqûre with drugs |journal=Journal of the Autonomic Nervous System |volume=14|issue=3|date=November 1985|page=214|last1=Feldberg|first1=W.|last2=Pyke|first2=D.|last3=Stubbs|first3=W. A.|doi=10.1016/0165-1838(85)90111-0|pmid=2866209 |access-date=12 May 2025|url-access=subscription}} In 1851, while examining the effects produced in the temperature of various parts of the body by each section of the nerve or nerves belonging to them, he noticed that division of the cervical sympathetic nerve resulted in more active circulation and more forcible pulsation of the arteries in certain parts of the head. A few months later, he observed that electrical excitation of the upper portion of the divided nerve had the contrary effect. This discovery of the vasomotor system also established the existence of both vasodilator and vasoconstrictor nerves.

Bernard's scientific discoveries were made through vivisection, of which he was the primary proponent in Europe at the time. In his description of the single-mindedness of scientists trying to prove their theories, he wrote: "[h]e does not hear the animals' cries of pain. He is blind to the blood that flows."{{cite book|page=309|url=https://books.google.com/books?id=i1mXs6qrRDcC&pg=PA309|title=Awe for the Tiger, Love for the Lamb: A Chronicle of Sensibility to Animals|isbn=9780774808972|last1=Preece|first1=Rod|author-link=Rod Preece|year=2002| publisher=UBC Press }} His use of vivisection disgusted his wife and daughters, who returned at home once to discover that he had vivisected the family dog.{{cite book|first=Mary|last=Midgley|title=Animals and Why They Matter|publisher=University of Georgia Press|year=1998|page=28|url=https://books.google.com/books?id=uE7lNzbN7wEC&pg=PA28|author-link=Mary Midgley|isbn=9780820320410}} The couple was officially separated in 1869 and his wife went on to actively campaign against the practice of vivisection.{{cite web|url=https://mskpain.center/news/role-women-history-animal-rights-movement|title=The Role of Women in the History of the Animal Rights Movement |last=Miller|first=Richard|date=24 March 2024|publisher=Chicago Center of Musculoskeletal Pain|access-date=12 May 2025}} Some in the scientific community were also uncomfortable with the practice. The physician-scientist George Hoggan spent four months observing and working in Bernard's laboratory, later writing that his experiences there had "prepared [him] to see not only science, but even mankind, perish rather than have recourse to such means of saving it."{{cite news | last = Hoggan | first = George | newspaper = Morning Post | date = 2 February 1875 | title = Letter}} Hoggan was a founding member of the National Anti-Vivisection Society in the mid-1870s.{{Cite book |last=Preece |first=Rod|author-link=Rod Preece|title=Animal Sensibility and Inclusive Justice in the Age of Bernard Shaw |publisher=UBC Press |year=2011 |isbn=9780774821124 |location=Vancouver |pages=113 |language=en}}{{cite book|last1=Bekoff|first1=Marc|author1-link=Marc Bekoff|last2=Meaney|first2=Carron A.|date=2013|title=Encyclopedia of Animal Rights and Animal Welfare|publisher=Routledge|pages=313–314|isbn=978-1-57958-082-7}}

Milieu intérieur, the "internal environment", is the key concept with which Bernard is associated. He explained that the body is "relatively independent" of the outside world, and that a healthy "internal environment" adapts to deficiencies in the surrounding environment, thus keeping the physiology balanced.{{cite book|last=Bernard|first=Claude|title=Lectures on the Phenomena of Life Common to Animals and Plants|date=1974|publisher=Charles C Thomas|location=Springfield, Ill.|isbn=0-398-02857-5|page=84 |translator-first1=Hebbel E.| translator-last1=Hoff| translator-first2=Roger| translator-last2=Guillemin|translator2-link=Roger Guillemin| translator-first3=Lucienne| translator-last3=Guillemin}} This is the underlying principle of what would later be called homeostasis,{{cite book |last1=Ernst |first1=Gernot |title=Heart Rate Variability |date= 2013 |publisher=Springer Science & Business Media |isbn=978-1-4471-4309-3 |page=4 |url=https://books.google.com/books?id=f368BAAAQBAJ |language=en}} a term coined by Walter Cannon.

Bernard was also interested in the physiological action of poisons, particularly curare and carbon monoxide gas. He is credited with first describing carbon monoxide's affinity for hemoglobin in 1857,{{Cite journal|last=Otterbein|first=Leo E.|date=April 2002|title=Carbon Monoxide: Innovative Anti-inflammatory Properties of an Age-Old Gas Molecule|url=http://www.liebertpub.com/doi/10.1089/152308602753666361|journal=Antioxidants & Redox Signaling|language=en|volume=4|issue=2|pages=309–319|doi=10.1089/152308602753666361|pmid=12006182|issn=1523-0864|url-access=subscription}} although James Watt had drawn similar conclusions about hydrocarbonate's affinity for blood acting as "an antidote to the oxygen" in 1794 prior to the discoveries of carbon monoxide and hemoglobin.{{Cite book|last1= Watt |first1= James |author-link=James Watt|url=https://books.google.com/books?id=2QcAAAAAQAAJ|title=Considerations on the Medicinal Use of Factitious Airs: And on the Manner of Obtaining Them in Large Quantities|volume=2|page=2|date=1794|publisher=Bulgin and Rosser|language=en}}

Throughout his career, Bernard sought to establish the use in medicine of what would later become the scientific method.{{cite journal|url=https://acnr.co.uk/articles/claude-bernard/|title=History of Neurology: Claude Bernard |last=Pearce|first=J. M. S.|date=8 December 2017|journal=Advances in Clinical Neurosciences and Rehabilitation|doi=10.47795/ZXLV9488|page=|access-date=12 May 2025|doi-access=free}} In An Introduction to the Study of Experimental Medicine (1865),{{cite book|last=Bernard|first=Claude|title=Introduction à l'étude de la médecine expérimentale|url=https://archive.org/details/BIUSante_31054|year=1865|publisher=J.-B. Baillière|location=Paris}} he emphasized the importance of trusting evidence over clout, even if it "contradicts a prevailing theory,"Bernard (1957), p. 164. as "[t]heories are only hypotheses" proven or disproven by facts.Bernard (1957), pp. 56, 165. He criticized scientists who cherry-picked their data only to prove their own hypotheses.Bernard (1957), p. 38. Unlike many scientific writers of his time,{{cn|date=May 2025}} Bernard wrote using the first person when discussing his own experiments and thoughts.Bernard (1957)

References

External links

{{Gutenberg author |id=6553| name=Claude Bernard}}
{{FadedPage|id=Bernard, Claude|name=Claude Bernard|author=yes}}
{{Internet Archive author |sname=Claude Bernard}}
[http://vlp.mpiwg-berlin.mpg.de/references?id=per50 Biography, bibliography, and links on digitized sources] in the Virtual Laboratory of the Max Planck Institute for the History of Science
[http://www.claude-bernard.co.uk 'Claude Bernard': detailed biography and a comprehensive bibliography linked to complete on-line texts, quotations, images and more.]
[https://web.archive.org/web/20130217164308/http://www.claude-bernard.co.uk/page2.htm The Claude Bernard Museum]
{{in lang|fr}} [https://web.archive.org/web/20120712102822/http://web2.bium.univ-paris5.fr/livanc/?intro=clber Claude Bernard's works] digitized by the [http://www.bium.parisdescartes.fr BIUM (Bibliothèque interuniversitaire de médecine et d'odontologie, Paris)], see its digital library [https://web.archive.org/web/20141007025741/http://www.bium.univ-paris5.fr/histmed/medica.htm Medic@].