Joseph Raphson

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Bond signed by Joseph Raphson on his admittance to the Royal Society

Joseph Raphson was an English mathematician known best for the Newton-Raphson method. Little is known about Raphson's life- even his exact birth and death years are unknown, though the mathematical historian Florian Cajori supplied the approximate dates 1648-1715. Raphson attended Jesus College in Cambridge and graduated with an M.A. in 1692. Raphson was made a Fellow of the Royal Society in 30 November 1689 after being proposed for membership by Edmund Halley.

Raphson's most notable work was Analysis Aequationum Universalis which was published in 1690. It contained the Newton-Raphson method for approximating the roots of an equation. Isaac Newton developed the same formula in the Method of Fluxions. Although Newton's work was written in 1671, it was not published until 1736- nearly 50 years after Raphson's Analysis . Furthermore, Raphson's version of the method is simpler and therefore superior, and it is this version that is found in textbooks today.

Raphson was a staunch supporter of Newton's claims as the inventor of Calculus against Gottfried Leibniz's. In addition, Raphson translated Newton's Arithmetica Universalis into English. The two were not close friends however, as evidenced by Newton's inability to spell Raphson's name either correctly or consistently.

[edit] Reference

Joseph Raphson, F.R.S. David J. Thomas; Judith M. Smith. Notes and Records of the Royal Society of London, Vol. 44, No. 2. (Jul., 1990), pp. 151-167.