How do we know it's Monday?

How do we really know it's Monday?

I'll give it to you that our traditional 7 day week is based on the creation account from the Bible involving 6 days of work and one of rest. (And the Sabbath is Saturday, not Sunday people.) But from that time to this how do we know we haven't gotten off a day.

I just think the time scale is too long for people to have not messed up. I mean the yearly calendar we know to be off by at least 4 years. Surely, we dropped day here or there.

I'm sure everyone has had a conversation like this.

Doug: Is it Tuesday or Wednesday?
Arnold: Uhm... it's Monday, Doug.

But what if a bunch of people had the same problem simultaneously and nobody knew the answer?

Doug: Is it Tuesday or Wednesday?
Arnold: Uhm... it's Tuesday Doug.
(But it's really Monday.)

This feeling happens a lot near a bank holiday. You have Monday off so Tuesday feels like Monday. Wednesday feels like Friday. Then the following Sunday feels like Saturday so you have to call in sick Monday and the cycle repeats.

Doug: Is it Labor day or Memorial day?
Arnold: Arbor Day and Boxing Day, baby, four day weekend!

Probably in this digital age these problems won't happen. I'm more worried that we are living based on the mistakes of the past. What about those long periods of history where things were spotty at best, like the Dark Ages?

Doug: What day is it?
Arnold: How should I know I can't see my watch.

Or worse, what if a king made a mistake, and it was like the Emperor's New Clothes, nobody could correct him. It would be Wednesday, but the king thinks Thursday so... so be it!

Doug: Hail King Arnold!
Arnold: Hail yourself, where is my Royal Thursday
Midafternoon Soup? If it is late I'll have to behead someone on Friday!
Doug: Riiight... I'll go ask Jeff about that immediately. For sooth!

And of course there was a lot of BC before we got to the messed up monk's AD years. All that BC stuff could have gone very badly. What if two tribes met up who hadn't seen each other for years?

Doug: Greetings western-dirt-gathering-nomad tribe, is this not a fine
Saturday.

Arnold: Greeting eastern-rock-hunting-nomad tribe, this is not a
fine Saturday, yesterday was. This is Sunday, put on some slacks it's time
for church.

You see?! We have no idea what today is. If today could really be Saturday, I better take the day off just in case.

Does anybody really know what time it is?
Does anybody really care?
- Chicago

Doug: I think ending with a quote from Chicago was a good move.
Arnold: You would, do you still want to get together Wednesday?
Doug: Tomorrow?
Arnold: No, the day after.
Doug: Sure, I guess, but it sounds like somebody's got a "case of the Mondays."
Arnold: At least I know what day it is.
Doug: Do you Arnold? Do you?
Arnold: You just want the last word on the blog don't you.
Doug: Is everything a competition for you?
Arnold: Fine have the last word, I'm waiting.
Doug: (shakes his head)
Arnold: Fine, and forget about getting together Wednesday!
Doug: No skin off my nose, I was busy tomorrow anyway!