A rather famous American president once gave a speech in which he started: “Four score and seven years ago…” thus raising the interesting question of what is “score” and how do we count in English?
To understand the meaning of “score,” let’s go to rural Scotland, away from the English-speaking tourists and listen to a shepherd as he counts his sheep:
“yan, tan, tether, mether, pimp (5), sether, hether, hother, dother, dick (10), yan dick, tan dick, tether dick, mether dict, bumfit (15), yana bumfit, tana bumfit, tetherer bumfit, metherer bumfit, giggot (20).”
What we see here is a method of counting things using four tallies of five up to twenty. This is known as “scoring” and hence “score” is used to mean a count of twenty.
For many traditional Native Americans counting with a base 20 was considered natural, after all, humans usually have 20 digits (hint: fingers and toes). Using a base ten was seen as using only half a count.
In ancient Babylon, counting was done using a base 60. However, numbers below 60 are clustered in groups of ten. This Babylonian system of base 60 has survived in English with regard to time (60 minutes in an hour) and in geometry (360 degrees in a circle).
English uses a base 10 for counting. Essentially, there are discrete numbers for 1 through 10. In a base 10 system, we would expect that the next ten numbers would be some form of ten plus one, ten plus 2, ten plus 3, etc. In the written number form, this seems to be the case: 11, 12, 13, and so on. But in the spoken form, there is a problem: while thirteen carries the ten marker (“teen”), eleven and twelve do not. Where did these numbers come from?
Before jumping to the conclusion that at some distant time, English used a base 12 (no, we were not visited by six-fingered ancient aliens), let’s look at the etymology of eleven and twelve.
“Eleven” comes from the Old English “endleofan” which means “one left” implying one over ten. This, in turn, is based on the Proto-Germanic “*ainlif” which comes from the Proto-Indo-European compound of “*ain” meaning “one” plus “*leikw-” mean “leave, remain.”
The etymology of “twelve” is similar to “eleven.” It comes from the Old English “twelf” meaning “two left” which comes from the Proto-Germanic “*twa-lif.”
Outside of Germanic, the only other instance of this “left over” counting system is Lithuanian which uses –lika (“left over”) and continues the series to 19. Lithuanian is generally considered to be the most conservative living Indo-European language and has retained many features of Proto-Indo-European which have been lost in other Indo-European languages.
In grouping numbers beyond ten, English uses the ending “-ty” (twenty, thirty, forty, etc) which means “ten.” This comes from the Old English “-tig.”