![\"Daniel](\"http:\/\/blogs.ams.org\/mathgradblog\/files\/2016\/05\/Daniel-Walls_925508_assignsubmission_file_Sh-to-ch-to-x-DW.png\")
<\/a>From \u201csh\u201d to \u201cchi\u201d to X Images from TED.com<\/p><\/div>\n
Find x. Well, we have found it several times as mathematicians, used it several times in problems, and assumed it as the universal unknown. The unknowns span from just a mathematics variable and into popular culture, spanning the X-files, the X-factor, and Project X. But where did we get x? In a TEDx (again, why x?) talk, Terry Moore<\/a> presents a brief explanation of what he has found is the reason we use x, and the reason is perhaps more comical than expected.<\/p>\n <\/p>\n Moore explained that he undertook learning Arabic to better understand the history of mathematics. He explains that the word \u201cshalan\u201d translates to \u201csomething,\u201d as in something unknown or something arbitrary. He goes on to explain that when the Europeans, mainly the Spanish, came to translate the Arabic mathematical findings, they were presented with a problem: the Spanish did not have a sound for \u201csh.\u201d Therefore, they picked a hard \u201cch\u201d\/\u201dck\u201d sound, as in the Greek \u201cChi\u201d, symbolized as \u201cX\u201d, which, when translated to Latin became \u201cx.\u201d Moore jokes at the end, \u201cWhy is it that X is the unknown?\u00a0X is the unknown\u00a0because you can’t say \u2018sh\u2019 in Spanish.\u201d<\/p>\n Having watched this video, I was inspired to ask, \u201cWhat other notation have we taken for granted?\u201d I then went and thought about why we use symbols. While yes, mathematics could be done with entirely words and documented arguments, the use of symbols stems from our use of language. Terrence W. Deacon explains in her book \u201cThe Symbolic Species,\u201d that we, as humans, have developed symbols that \u201cdon’t just represent things in the world, they also represent each other. Because symbols do not directly refer to things in the world, but indirectly refer to them by virtue of referring to other symbols, they are implicitly combinatorial entities whose referential powers are derived by virtue of occupying determinate positions in an organized system of other symbols\u201d (99). The use of symbols (variables) to describe other symbols (words, or other variables) has become a part of our general nature.<\/p>\n Besides from x, a symbol perhaps most used by mathematicians is the equal sign, =. What does this mean and how did it evolve? Until about 400 years ago, there were numerous symbols that meant equal. At first, there was no sign for equal, but rather it expressed rhetorically with such words as aequales<\/em>, faciunt<\/em>, or gleich<\/em>, taking form in a variety of languages. At one point, just the abbreviation aeq <\/em>was used. As a variety of other mathematical notations had formed, so did a multitude of ways to write an equals sign. Buteo used [ to show the function of equality, and Diophantus used two parallel lines, ||, to show that two quantities were equal. Descartes suggested that\u00a0 Up to the 17th<\/sup> century, the =\u00a0symbol had a plethora of meanings, including parallel lines, difference, or even plus or minus. In Berlinghoff and Gouvea\u2019s Math through the Ages<\/em>, it is noted that the symbol is suggested by Recorde in the 15th<\/sup> century, but not adopted for a couple hundred years later until Leibniz preferred = to other symbols in his calculus notation, which had proven to be more successful than Newton\u2019s. Just think, if we had used Newton\u2019s calculus notation, we would still be using\u00a0 So Leibniz wins! And therefore so does Recorde and the traditionally accepted sign, =, is now used in all of the textbooks.<\/p>\n References:<\/a> be used to signify equality, and, for a while, he had begun to gain some popularity for this notation\u2014as well as developing a widely, used coordinate system. (Cajori 297-301)<\/p>\n<\/a> instead of =. (100)<\/p>\n
\nBerlinghoff, William P.Gouv\u00eaa, Fernando Q.Math Through The Ages: A Gentle History For Teachers And Others<\/em>. Farmington, ME : Oxton House Publishers ; 2004. Print.
\nCajori, Florian.\u00a0A History Of Mathematical Notations<\/em>. New York : Dover Publications, 1993. Print.
\nDeacon, Terrence William.\u00a0The Symbolic Species: The Co-evolution Of Language And The Brain<\/em>. New York : W.W. Norton, 1997. Print.
\nMoore, Terry. \u201cWhy is \u2018x\u2019 the unknown?\u201d TED<\/em>. Feb 2012. Accessed 28 March 2016. http:\/\/www.ted.com\/talks\/terry_moore_why_is_x_the_unknown<\/p>\n