Correction Calendar Notation
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Correction Calendar Notation: Correcting the time difference calculation by taking into account that there is no year 0
- I told you in the last video on calendar notation that ,
- regardless of whether you're using BC/AD or BCE and CE,
- that there is no year zero,
- that we had 1BC and then we had that theoretical birth of Jesus
- and most historians don't think he was born right exactly on 1 January 1AD
- but there is no year zero
- right after that you go from December 31st 1BC to January 1st 1AD.
- There's no year zero.
- And despite the fact that I emphasized in the last video,
- I didn't take that into consideration when I calculated
- how many years there were between|Plato's birth and Columbus' discovering the New Wolrd
- The reason why I didn't take that into consideration
- is that the year 1492, whether you want to call it AD 1492, Anno Domini 1492,
- whether you wanna call it that or you wanna call it 1492 in the Common Era
- it's not 1492 years since the theoretical birth of Jesus,
- which we know is not the actual birth. He was probably born before that.
- It is 1491 years since the birth of Jesus.
- And to think about it this way, let's just assume I'll the theoretical date we're talking about here
- or this theoretical event, this kind of birth of Jesus that our calendars evolve around
- If we talk about January 1, let's think about it this way, so January 1 in the Common Era,
- how long is that since the birth of Jesus? It's not 1 year.
- You wouldn't just look at this and say it's been 1 year, because this is theoretically the day that he was born.
- So this is zero years, or almost zero years since that theoretical birth of Jesus.
- Another way to think about it is: How long after January 1 the year 1BCE, and I can call this AD and I can call this BC,
- what's the time difference between these two days?
- So, the way I calculated it before I said "Oh, this is one year after that theoretical birth" that's wrong.
- This is during that theoretical birth.
- But if did the way I did in the last video, I said "Oh, this is one year after, this is one year before
- you add them together and you would get two." But that's wrong.
- Because there is no year zero.
- So January 1 1AD, or 1CE is right over here and then January 1 1BCE is exactly one year before that.
- So there's only one year. One year difference.
- And the reason why the math is strange is there is no year zero.
- If there was a year zero, then my calculation in the last video is correct.
- So really, the way that you would calculate the time between Plato's birth at 428BC
- and Columbus sailing across the Atlantic in 1492
- you would say "ok, this is 428 years before that theoretical birth of Christ
- but this isn't 1492 years after that theoretical birth.
- This is 1492 minus one. So what you do is you add these two numbers
- this is 428 before, this is 1492 minus one years after
- so you would add them and then subtract one, so the correct answer - this is the correction part
- it isn't 1920 years between Plato's birth and Columbus.
- It is, we wanna subtract one from that,
- it is 1920 minus one years, so that is 1919 years.
- The same way that the difference between 1AD and 1BCE,
- you would say, you could almost do this in positive and negative numbers, you say:
- "Oh, this is positive one minus negative one and that would give me two, but there is no zero
- so you just subtract another one, so this is exactly one year difference.
- Just wanted to clarify that. That's what that "no year zero" stuff does.