# List of misnamed theorems

This is a list of misnamed theorems in mathematics. It includes theorems (and lemmas, corollaries, conjectures, laws, and perhaps even the odd object) that are well known in mathematics, but which are not named for the originator. That is, these items on this list illustrate Stigler's law of eponymy (which is not, of course, due to Stigler, who credits Merton).

• Cramer's paradox. This was first noted by Colin Maclaurin in 1720, and then rediscovered by Leonhard Euler in 1748 (whose paper was not published for another two years, as Euler wrote his papers faster than his printers could print them). It was also discussed by Gabriel Cramer in 1750, who independently suggested the essential idea needed for the resolution, although providing a rigorous proof remained an outstanding open problem for much of the 19th century. Even though Cramer had cited Maclaurin, the paradox became known after Cramer rather than Maclaurin. Halphen, Arthur Cayley, and several other luminaries contributed to the earliest more or less correct proof. See [8] for an excellent review.
• Cramer's rule. It is named after Gabriel Cramer (1704–1752), who published the rule in his 1750 Introduction à l'analyse des lignes courbes algébriques, although Colin Maclaurin also published the method in his 1748 Treatise of Algebra (and probably knew of the method as early as 1729).[9]
• Frobenius theorem. This fundamental theorem was stated and proved in 1840 by Feodor Deahna.[10] Even though Frobenius cited Deahna's paper in his own 1875 paper,[11] it became known after Frobenius, not Deahna. See [12] for a historical review.
• Heine–Borel theorem. This theorem was proved in 1872 by Émile Borel, not by Eduard Heine. Borel used techniques similar to those that Heine used to prove that continuous functions on closed intervals are uniformly continuous. Heine's name was attached because Schönflies noticed the similarity in Heine's and Borel's approaches. In fact, the theorem was first proved in 1852 by Peter Gustav Lejeune Dirichlet, but Lejeune Dirichlet's lecture notes were not published until 1904.[13]
• Marden's theorem. This theorem relating the location of the zeros of a complex cubic polynomial to the zeros of its derivative was named by Dan Kalman after Kalman read it in a 1966 book by Morris Marden, who had first written about it in 1945.[15] But, as Marden had himself written, its original proof was by Jörg Siebeck in 1864.[16]
• Morrie's law. The name is due to physicist Richard Feynman, who used to refer to the identity under that name. Feynman picked that name because he had learned the law during his childhood from a boy with the name Morrie Jacobs.[17]
• Pell's equation. The solution of the equation x2 − dy2 = 1, where x and y are unknown positive integers and where d is a known positive integer which is not a perfect square, is ascribed to John Pell. It seems to have been discovered by Fermat, who set it as a challenge problem in 1657. The first European solution is found in a joint work in 1658 by John Wallis and Lord Brouncker; in 1668, a shorter solution was given in an edition of a third mathemathetician's work by Pell; see [18] The first rigorous proof may be due to Lagrange. The misnomer apparently came about when Euler confused Brouncker and Pell; see [19] for an extensive account of the history of this equation.
• Poincaré lemma. This was mentioned in 1886 by Henri Poincaré,[20] but was first proved in a series of 1889 papers by the distinguished Italian mathematician Vito Volterra. Nonetheless it has become known after Poincaré. See [12] for the twisted history of this lemma.
• Pólya enumeration theorem. This was proven in 1927 in a difficult paper by J. H. Redfield.[21] Despite the prominence of the venue (the American Journal of Mathematics), the paper was overlooked. Eventually, the theorem was independently rediscovered in 1936 by George Pólya.[22] Not until 1960 did Frank Harary unearth the much earlier paper by Redfield. See [23] for historical and other information.
• Stokes' theorem. It is named after Sir George Gabriel Stokes (1819–1903), although the first known statement of the theorem is by William Thomson (Lord Kelvin) and appears in a letter of his to Stokes. The theorem acquired its name from Stokes' habit of including it in the Cambridge prize examinations. In 1854 he asked his students to prove the theorem in an examination; it is not known if anyone was able to do so.[24]
• Zorn's lemma is named for Max Zorn. Much work on the theorem now known as Zorn's lemma, and on several closely related formulations such as the Hausdorff maximal principle, was done between 1907 and 1940 by Zorn, Brouwer, Hausdorff, Kuratowski, R. L. Moore, and others. But the particular theorem now known as "Zorn's lemma" was never proved by Zorn, and in any event Zorn's results were anticipated by Kuratowski. The theorem was discovered by Chevalley in 1936, and published and attributed to Zorn by him in Bourbaki's Théorie des Ensembles in 1939. A very similar result was anticipated by S. Bochner in 1928.[25]

## References

1. ^ Newcomb, S. (1881). "Note on the frequency of use of the different digits in natural numbers". Amer. J. Math. (The Johns Hopkins University Press) 4 (1): 39–40. doi:10.2307/2369148. JSTOR 2369148.
2. ^ Benford, F. (1938). "The law of anomalous numbers". Proc. Amer. Phil. Soc. 78: 551–572.
3. ^ Hill, Theodore P. (April 1995). "The Significant Digit Phenomenon". Am. Math. Monthly (Mathematical Association of America) 102 (4): 322–327. doi:10.2307/2974952. JSTOR 2974952.
4. ^ Feller, William (1968), An Introduction to Probability Theory and its Applications, Volume I (3rd ed.), Wiley, p. 69.
5. ^ Bix, Robert (1998). Conics and Cubics. Springer. ISBN 0-387-98401-1.
6. ^ Burnside, William (1897). Theory of groups of finite order. Cambridge University Press.
7. ^ Grattan-Guinness, Ivor (2002), Companion Encyclopaedia of the History and Philosophy of the Mathematical Sciences, Routledge, pp. 779–780, ISBN 9781134957507.
8. ^ Scott, Charlotte Agnas (March 1898). "On the Intersection of Plane Curves". Bull. Am. Math. Soc. 4 (6): 260–273. doi:10.1090/S0002-9904-1898-00489-5.
9. ^ Carl B. Boyer (1968). A History of Mathematics, 2nd edition. Wiley. p. 431.
10. ^ Deahna, F. (1840). "Über die Bedingungen der Integrabilität". J. Reine Angew. Math. 20: 340–350.
11. ^ Frobenius, Georg (1895). "Ūber das Pfaffsche Problem". J. Reine Angew. Math.: 230–315.
12. ^ a b Samelson, Hans (June–July 2001). "Differential Forms, the Early days; or the Stories of Deahna's Theorem and of Volterra's Theorem". Am. Math. Monthly (Mathematical Association of America) 108 (6): 552–530. doi:10.2307/2695706. JSTOR 2695706.
13. ^ Sundström, Manya Raman (2010). "A pedagogical history of compactness". arXiv:1006.4131v1 [math.HO].
14. ^ Thomas & Finney. Calculus and Analytic Geometry.
15. ^ Kalman, Dan (2008), "An Elementary Proof of Marden's Theorem", The American Mathematical Monthly 115: 330–338, ISSN 0002-9890
16. ^ Siebeck, Jörg (1864), "Über eine neue analytische Behandlungweise der Brennpunkte", Journal für die reine und angewandte Mathematik 64: 175–182, ISSN 0075-4102
17. ^ W.A. Beyer, J.D. Louck, and D. Zeilberger, A Generalization of a Curiosity that Feynman Remembered All His Life, Math. Mag. 69, 43–44, 1996.
18. ^ Cajori, Florian (1999). A History of Mathematics. New York: Chelsea. ISBN 0-8284-0203-5. (reprint of fifth edition, 1891).
19. ^ Whitford, Edward Everett (1912). The Pell Equation. New York: E. E. Whitford. This is Whitford's 1912 Ph.D. dissertation, written at Columbia University and published at his own expense in 1912.
20. ^ Poincaré, H. (1886–1887). "Sur les residus des intégrales doubles". Acta Math. 9: 321–380. doi:10.1007/BF02406742.
21. ^ Redfield, J. H. (1927). "The theory of group related distributions". Amer. J. Math. (The Johns Hopkins University Press) 49 (3): 433–445. doi:10.2307/2370675. JSTOR 2370675.
22. ^ Pólya, G. (1936). "Algebraische Berechnung der Isomeren einiger organischer Verbindungen". Zeitschrift für Kristallographie A 93: 414. doi:10.1524/zkri.1936.93.1.415.
23. ^ Read, R. C. (December 1987). "Pólya's Theorem and its Progeny". Mathematics Magazine 60 (5): 275–282. doi:10.2307/2690407. JSTOR 2690407.
24. ^ Victor J. Katz (May 1979). "The History of Stokes' Theorem". Mathematics Magazine 52 (3): 146–156. doi:10.2307/2690275. JSTOR 2690275.
25. ^ Campbell, Paul J. (1978). "The Origin of ‘Zorn's Lemma’". Historia Mathematica 5: 77–89. doi:10.1016/0315-0860(78)90136-2.