Kristen Lippincott

The Mesopotamian calendar, the Mesopotamians were the great mathematicians of antiquity, and they were the ones who set up the 60 base number series.

Yes.

And so we have inherited it.

The Egyptians had a 10 base calendar, so we've inherited some from that calendar.

One of my favorites is the Aztec Mayan calendar, which is actually 20 day weeks.

And their year was a ritual year, which is 260 days.

And some people have said it might be related to the amount of time it takes an infant to come to full term before it's born, which is nine months.

It might be

a period between two eclipses, which is about 260 days, or most people think it has to do with Venus, which reappears as the morning star every 263 days.

So everybody's looking for things that suit their particular religions or yearly cycles.

So they're all different until civilizations bring them together and say, no, we're going to have this kind of calendar.

And that's when people start to get really restrictive about how many days they are, how long they are, what the months are called.

Well, two words there that I would say don't quite fit with my thinking, scientific and rational.

Basically, it was emotional.

They wanted to get rid of the power of the Catholic Church, so they had to get rid of the old calendar so they could get rid of the saints' days.

So they said, let's return to a bucolic agricultural calendar and we'll call it, today is the day for growing grass or today is the day for picking grapes.

Even though it looks numerically, because it is decimal-based, as if it's quote-unquote scientific, it's actually, like most calendars, deeply emotional and culturally based.

And it didn't last?

No, because they were surrounded by countries who didn't keep that calendar, and it became really, really difficult when you're having any kind of international negotiations.

Well, historical throwback again, I wouldn't say that.