Understanding calendar notation Difference between BC, BCE, AD and CE. A little bit about the birth of Jesus as well.
Understanding calendar notation
- This right here is a fresco by Raphael of Plato hanging out with his best student Aristotle
- And you may or may not know that these two fellows along with Plato's teacher Socrates
- are considered the fathers of Western philosophy,
- but that's not what this video is about.
- This is actually just a small little video about different dates or better
- different ways to specify dates or dating machinisms.
- And so if you were to look up Plato's birth you might get either 428 or 427
- but we'll go with 428 -
- if you were to look up Plato's birth
- you might see it written as 428 BC
- or you might see it written as 428 BCE
- and the natural question is: what's the difference here?
- They both have BC but this one has an E and it's the same year right now.
- And the answer is that these are referring to the exact same year in history
- but the acronyms here do stand for different things.
- BC literally stands for Before Christ
- so the date is written 428 BC.
- The implication is that this is 428 years before the birth of Christ.
- We'll see in a second that that's not exactly right
- but that's what the implication is. If someone writes BCE
- they're saying something very different. The B still stands for before.
- So the B still stands for Before. But the CE. The C in CE does not stand for Christ anymore. It now stands
- for Common. And so the CE part is Common Era.
- Even though it's not referring to Christ any more, there is kind of intention here
- so that it is less religious than the term Before Christ
- it is still kind of putting an importance on Christ's birth
- because it is saying that the Common Era is the time period after the birth of Christ
- which we'll see in a second isn't exactly right
- but it's essentially the same exact dating sheme.
- One not directly referring to Christ,
- one that is directly referring to Christ.
- Similarly, this right here is a painting of Christopher Columbus
- and if you would look up in history books
- you'd know what was his first voyage
- and when did he first show up in the New World
- fighting an island in the Bahamas you would see it written as
- either 1492 or AD 1492
- or 1492 CE.
- And once again these are all referring to the same year
- just using different acronyms.
- One of them is a little bit more religious
- or more directly refers to Christ
- and one is a little less religious.
- So AD some people think it refers to After Death --
- it does not refer to After Death.
- Because if you think about it if you have years before the Christ and
- if you start numbering years after his death how would you number the years during his life?
- So AD does not stand for After Death.
- It stands for Anno Domini.
- Which literally means -- Anno means year
- and Domini means Lord or the Lord or the year of our Lord
- and one anno domini 1 AD would be the year of Jesus Christ's birth
- so not after death, it stands for Anno Domini
- but literally Year of our Lord, so year since that Jesus was born.
- With year one being the... implicitly starting with his birth.
- And we'll see in a second that's not exactly right.
- CE stands for Common Era.
- Once again, 1 CE is the same thing as AD 1,
- sometimes, we now write AD 1492 or we write 1492 AD,
- all referrig to the exact same thing.
- Now, all of these things refer to... you know, when we say 428 BC
- it implies 428 years before the birth of Christ,
- 1492 AD that's in the Year of our Lord 1492
- and it implies 1492 years since the birth of Christ,
- but the reality is that we're not really quite sure
- when Christ was born and so these aren't exactly.
- You know, Columubus didn't sail across the Atlantic
- exactly 1492 years after the birth of Christ.
- Most historians put the birth of Christ at 7-2 BC or BCE
- depending on how you want to view it.
- Remember, BC is Before Christ, which is little ironic,
- because we're talking about the actual birth of Christ,
- BCE is Before the Common Era.
- And they put his death at 30-36 AD which is 30-36 in the Year of our Lord,
- that's what this stands for, Anno Domini,
- or in the Common Era, CE.
- Now, some people they obviously don't like the BC/AD naming mechanism
- because it's explicitly referring to Christ and every year
- it makes Christ the central figure in all of history,
- so they'll say this is clearly too Christian
- and they would prefer the less Christian naming scheme
- where we use BCE and CE.
- But lot of people would still say: hey look, ok, you changed... or, you know
- first of all some Christians wouldn't like this
- that you removed the direct references to the birth of Christ
- or being the years since Christ's birth,
- but even here some people would complain that
- althought you've removed the direct reference
- that this is saying Before the Common Era and the Common Era,
- even though you've removed the direct reference, it still makes Christ's birth
- the central thing in all of history.
- But this is the convention whether people like it or not
- in order to have the same reference point
- and theologically it's difficult to switch it, this time,
- every one has essentially settled on this.
- So it's really just a matter of letters,
- which naming scheme you pick.
- The whole point of this video is that you don't get
- confused between BC and BCE, that you don't think that
- AD stands for After Death, it stands for Anno Domini,
- the Year of the Lord or the Year of our Lord
- and CE stands for Common Era.
- This and this are referring to essentially the same count,
- after the birth of Christ, or the theoretical birth of Christ
- which we don't really know when it actually happened,
- it probably did not happen at the beginning of 1 AD or 1 CE.
- These two things both also refer to the same direction in the timeline.
- One last thing I want to point out is that
- there is no year zero.
- So if you take either of these naming schemes, you have...
- so let's go very close to the years one.
- So there is at some point this theoretical birth of Christ
- which is probably not the actual birth of Christ,
- but at that theoretical point, right at that point
- you have 31 December of the previous year,
- all of sudden now you have 1 January 1 AD or CE
- and the year before that was 1 BC or BCE,
- depending on how you wanna refer to it.
- So there is no year zero in this scheme.
- And the last thing I want to emphasize,
- and it might be obvious to you,
- is the larger number you have here,
- the further back you're going in time.
- Because this is saying how many years
- before this theoretical birth of Crhist,
- and obviously, the larger numbers the further you're going off
- into the future. And if you want to figure out
- how many years passed between Plato's birth
- and Columbus's sailing across the Atlantic to find the New World,
- you would say: well, look at it, it took 428 years to go
- form Plato's birth to this theoretical birth of Christ
- and there is another 1492 years to wait until Columbus gets his ships together,
- so the total number of years would be,
- 428 years to get to Christ from Plato's birth
- and then you have another 1492 years to wait for Columbus,
- so it's eight plus two, that is ten,
- as you can see I just want to add a little arithmetic in this video,
- so one plus two plus nine is twelve,
- and then we have nine, one plus four plus four...
- so 1920 years between the Plato's birth
- and Columbus sailing across the Atlantic.
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At 5:31, how is the moon large enough to block the sun? Isn't the sun way larger?
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