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The phases of the moon cycle every ~29.5 days [1], so you could use those to make an argument that a ~7-day week is pretty "natural." One could imagine early h
by q7xvh97o2pDhNrh 3y ago
The phases of the moon cycle every ~29.5 days [1], so you could use those to make an argument that a ~7-day week is pretty "natural."
One could imagine early humans being much more aware of the phase of the moon (whereas I haven't even seen that thing in months), and the 29.5 day cycle naturally splits into two pieces, since it's (new moon) -> (full moon) -> (new moon).
And one could also imagine people were pretty aware of when they were halfway between a new moon and a full moon — so now we've naturally arrived at a rough time interval of 29.5/4 = ~7 days.
[1]: https://spaceplace.nasa.gov/moon-phases/en/ https://spaceplace.nasa.gov/moon-phases/en/
- HPsquared 3y agoDoesn't that mean a 10-day week (3 weeks per month) is a better fit? Only 0.5 days out instead of 1.5. Edit: though with the sinusiodal variation in the moon, I guess it makes sense to divide it into 4. 3 weeks doesn't make sense for that.
- em500 3y agoWe even have words for the halfway phases between new moon and full moon: first quarter and last quarter. The 7 day week is not directly derived from natural cycles (unlike the month and year lengths), but the moon phases are convenient synchronization points for (approximately) 7 day cycles.