12/Historical Note
Historical Note on $12$ (Twelve)
There are many occurrences of the number $12$ in various cultures in history:
- There are $12$ months in a year, divided into $4$ seasons of $3$ months each.
- There are $12$ signs of the Zodiac, divided into $3$ sets of $4$ each, and categorising them another way, into $4$ sets of $3$ each.
- There are $12$ hours in each day and in each night.
- There are $12$ semitones in an octave of a well-tempered scale.
- There are $12$ inches in a foot.
- There were $12$ pence in $1$ shilling in pre-decimal British coinage.
The word dozen, now falling into disuse, means a set of $12$.
Also see
- Definition:Duodecimal System
Sources
- 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $12$
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $12$