Georges-Louis Leclerc, Comte de Buffon

1. Georges-Louis Leclerc, Comte de Buffon 1707-1788

2. Buffon’s Life • -eldest of five children • -born into a wealthy family, mother was well-educated • -Georges-louis Leclerc was his name until 1725 • his mother inherited a large sum of money when Georges was ten years old that allowed his father, benjamin, to become lord of Buffon and Montbard • Georges attended Jesuit College of Godrans in Dijon • brothers joined the church but Georges’s father wanted him to study law • didn’t do well in school, but did show talent for mathematics

3. Buffon’s Life Continued -At age 20, he began calling himself Georges-louis Leclerc de Buffon and also discovered the binomial theorem -one of the most powerful figures in the court of King Louis XV -July 1739: appointed as keeper of the royal botanical garden (Jardin du Roi) -expanded gardens to current 64 acres

4. Histoire Naturelle -encyclopedia account of natural world -wanted to have 50 volumes but only 36 completed before death

5. Modern Scientific Mind • Buffon believed that things happened through natural phenomena • Rejected Newton’s idea that planets’ motions were direct consequence of god’s intervention • Instead believed that the creation of the planets involved a collision of a comet with the sun • Model doesn’t work, but at least his model followed the law of mechanics • Believed that life came about on earth through the appearance of organic matter • “first to create an autonomous science, free of any theological influence”

6. Buffon vs. Linnaeus Linnaeus and most contemporaries had biblical understanding of nature, thought species survived unchanged from god’s creation in garden of eden Buffon thought it was ridiculous to imagine god being “very busy with the way a beetle’s wings should fold”, he believed species were groups of animals that were breeding together and changing over time Linnaeus was inventing classification while Buffon was more interested in habitat and behavior, predicting sciences like ecology and ethology (200 years in future)

7. Buffon Linnaeus Rivalry Buffon enjoyed pointing out flaws in Linnaeus’s classifications, like putting both humans and two-toed sloths in the anthropomorpha order Linnaeus named a weed genus Buffonia

8. Work with Probability Origin of “stochastic” probability -“Stochastic”: a variety of techniques that are based on a common feature: using random numbers to make predictions possible Famous needle experiment: -repeatedly tossed a needle at random onto a board ruled with parallel straight lines - derived probability that the needle would intersect a line

9. Probability Buffon made the leap from probabilities calculated by counting (discrete sample spaces) to probability involving measuring First person to use geometry and newly invented tools of calculus to study probability

10. Age of the Earth Believed that earth originated as a fireball, solidifying as it cooled down Experiment: estimating the age of the earth Different size balls of molten iron, watched how long they took to cool down Numbers he came up with: 10 million years-75,000 years (final estimate) Opened eyes of educated people to vast span of geologic time Beginning of the end of the idea that everything was created just 6,000 years ago, to the garden of Eden

11. Buffon Criticized -not greatly admired during his lifetime -criticized by Voltaire and others -snubs from mathematicians, chemists, astronomers, naturalists -public admired him, however -he reacted with dignity, didn’t get into disputes -Darwin later praised him as the first person to treat evolutionary ideas “in a scientific spirit” -opened the door for evolutionary thinking -he was mostly forgotten except for…

12. A statue of Georges-louis Leclerc, Comte de Buffon in the Jardin du Roi

13. Summary • Buffon had a modern scientific mind and was very forward thinking • He and Linnaeus were rivals • He wrote 36 volumes of Histoire Naturelle • He did a lot of work with probability and determining the age of the earth • He was criticized in his time and largely forgotten

14. References • Conniff, Richard. "Forgotten, Yes. But Happy Birthday Anyway." The New York Times • 30 Dec. 2007: 5. Academic Search Premier. 14 Sept. 2008 <http://researchport.umd.edu:80/v/7u897ehvvq1318dyih2ycrjd6r1ak6eemiugprq3myld18a1le-18500?func=quick-3&short-format=002&set_number=024093&set_entry=000002&format=999>. • "Georges-Louis Leclerc, Comte de Buffon." University of California Museum of Paleontology. 15 Sept. 2008 <http://http://www.ucmp.berkeley.edu/history/buffon2.html>. • Gianpietro Malescio. "Predicting with Unpredictability." Nature 434 (2005): 1073. Academic Search Premier. 14 Sept. 2008 <http://researchport.umd.edu:80/v/agi534uanjsjdv2u1nnmve1vfnbkd2uuxsakvvahf4limhftcq-27681?func=quick-3&short-format=002&set_number=024181&set_entry=000001&format=999>. • O'Connor, JJ, and EF Robertson. "Georges Louis Leclerc Comte de Buffon." The MacTutor History of Mathematics Archive. University of St. Andrews Scotland. 13 Sept. 2008 <http://http://www-history.mcs.st-andrews.ac.uk/biographies/buffon.html>. • Turner, Paul. "Coin on a Chessboard." Australian Mathematics Teacher 62 (2006): 12. Academic Search Premier. 14 Sept. 2008 <http://researchport.umd.edu:80/v/agi534uanjsjdv2u1nnmve1vfnbkd2uuxsakvvahf4limhftcq-04701?func=quick-3&short format=002&set_number=024220&set_entry=000002&format=999>.