# Is There Any Logic to Roman Numerals?

**URL:** <https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696>\
**Category:** Factual Questions\
**Created:** [October 28, 2004, 5:44pm UTC](https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696 "2004-10-28T17:44:34Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Jim\_B](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jim_b/32/4338_2.png) [@Jim\_B](https://boards.straightdope.com/u/Jim_B)\
**Post date:** [October 28, 2004, 5:44pm UTC](https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696/1 "2004-10-28T17:44:34Z")

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I=1, V=5, X=10, L=50, C=100, M=1000. Why? Outside of the fact “I” resembles our 1 a little, I can’t see any connection here. Plus I know the Roman alphabet was pretty similiar in location to the letters of our alphabet. And these values asigned to them obviously bear no relation to their position in the alphabet. Does anyone know how Roman letters got their values?

🙂

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**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\
**Post date:** [October 28, 2004, 5:58pm UTC](https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696/2 "2004-10-28T17:58:00Z")

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“I” represented one finger, for one. “V” represented an open hand, i.e. five fingers. Two "V"s make an “X” (although this origin is apparently only one of several theories).

“C” stands for _centum_ (100), and “M” stands for _mille_ (1,000).

I’m not sure about the “L”, “D” etc. Hmm, here’s a cite with some more info: [http://mathforum.org/library/drmath/view/57547.html](http://mathforum.org/library/drmath/view/57547.html)

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**Author:** ![Giles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/giles/32/60_2.png) [@Giles](https://boards.straightdope.com/u/Giles)\
**Post date:** [October 28, 2004, 6:08pm UTC](https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696/3 "2004-10-28T18:08:35Z")

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You can think of the L (50) as the lower half of the C.

The M could be written as CIC, with the second C reversed. D is the second half of that, so D is roughly like half of M.

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**Author:** ![caveman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/caveman/32/7242_2.png) [@caveman](https://boards.straightdope.com/u/caveman)\
**Post date:** [October 28, 2004, 7:48pm UTC](https://boards.straightdope.com/t/is-there-any-logic-to-roman-numerals/271696/4 "2004-10-28T19:48:11Z")

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The numbers we use on a day-to-day basis are (modified) Arabic Numerals (1,2,3,4,5,6,7,8,9), and were developed seperately from their Roman counterparts. However, I imagine the shape of their symbols for one have similar origins.