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): $12$