God made the days and nights but man made the Calendar.
“In another meaning of the word, a calendar is an almanac, a program of future events or a record of past events, each assigned to a day or a year.”
“The calendar is thus a human invention…” – then there must be more than one way to invent it.
The trail of people using calendar
Travelling around, need cues to predict weather, food, etc. for survival.
-> learnt to grow crops and to domesticate animals – more reliable to seasons
-> cities, armies, civil engineering, tax, wars and empires … came into being, all of which call for a calendar
-> need for sacrifice and rituals emerged – should be recorded by calendar