# Bc, Ad, Wtf? **URL:** \ **Category:** Factual Questions\ **Created:** [February 15, 2007, 3:29pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351 "2007-02-15T15:29:48Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Buckwheat](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@Buckwheat](https://boards.straightdope.com/u/Buckwheat)\ **Post date:** [February 15, 2007, 3:29pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/1 "2007-02-15T15:29:48Z")
Please fight my ignorance. What exactly does BC and AD stand for, in the context of time? I will show my ignorance here and say that I thought BC stood for Before Christ, and AD stood for After Death (referring to Christ). However, one time I read that AD stood for Anno Domini (sp?) or something like that. Could someone please clarify all of this for me in a short, understandable answer? Thanks! ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [February 15, 2007, 3:32pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/2 "2007-02-15T15:32:56Z")
“Anno Domini” = “In the year of our Lord” See [Wiki](http://en.wikipedia.org/wiki/Anno_Domini) for details. ---
**Author:** ![Captain\_Amazing](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@Captain\_Amazing](https://boards.straightdope.com/u/Captain_Amazing)\ **Post date:** [February 15, 2007, 3:37pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/3 "2007-02-15T15:37:54Z")
AD does stand for Anno Domini, which is Latin for “In the Year of the Lord”. Around the year 500, this monk named Dionysis Exiguus decided there needed to be an accurate way of calculating dates, and he decided that dates should be calculated from the birth of Jesus. So, he figured out the date Jesus was born and called it AD 1 There’s a lot of evidence he got his calculations wrong, and that Jesus was really born sometime between 6-4 BC, but it’s what he calculated. ---
**Author:** ![Buckwheat](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@Buckwheat](https://boards.straightdope.com/u/Buckwheat)\ **Post date:** [February 15, 2007, 3:38pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/4 "2007-02-15T15:38:25Z")
Well I guess I wasn’t so far off. Thank you **silenus**! ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [February 15, 2007, 3:39pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/5 "2007-02-15T15:39:13Z")
I live to serve. 😃 ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [February 15, 2007, 3:39pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/6 "2007-02-15T15:39:58Z")
You’ll occasionally run across BCE as well. It’s for Before Common Era, which is a way of referencing the same timeframe as BC without offending infidels. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [February 15, 2007, 3:39pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/7 "2007-02-15T15:39:58Z")
The current trend, particularly in the sciences, is to replace AD and BC with CE (the Common Era) and BCE (Before the Common Era). ---
**Author:** ![FatBaldGuy](https://avatars.discourse-cdn.com/v4/letter/f/ecd19e/32.png) [@FatBaldGuy](https://boards.straightdope.com/u/FatBaldGuy)\ **Post date:** [February 15, 2007, 3:42pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/8 "2007-02-15T15:42:34Z")
Of course, the problem with having BC stand for Before Christ and AD for After Death, is that it leaves about 33 years unaccounted for (the years between the birth and death of Christ). Now it is becoming politically correct to use the terms CE and BCE (Common Era and Before Common Era) to avoid any reference to religion when referring to dates. P.S. On preview, it looks like I need to type faster. ---
**Author:** ![Buckwheat](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@Buckwheat](https://boards.straightdope.com/u/Buckwheat)\ **Post date:** [February 15, 2007, 3:50pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/9 "2007-02-15T15:50:15Z")
[QUOTE=Captain Amazing] AD does stand for Anno Domini, which is Latin for “In the Year of the Lord”. Around the year 500, this monk named Dionysis Exiguus decided there needed to be an accurate way of calculating dates, and he decided that dates should be calculated from the birth of Jesus. So, he figured out the date Jesus was born and called it AD 1 There’s a lot of evidence he got his calculations wrong, and that Jesus was really born sometime between 6-4 BC, but it’s what he calculated. [/QUOTE] Thank you Captain! So, here is a stupid assumption/joke: nobody would know what year it was during the BC time right? Like a person couldn’t say it was 53 BC because he didn’t know that in 53 more years Jesus would arrive, right? I am just wanting to clarify if I am understanding this correctly. ---
**Author:** ![FatBaldGuy](https://avatars.discourse-cdn.com/v4/letter/f/ecd19e/32.png) [@FatBaldGuy](https://boards.straightdope.com/u/FatBaldGuy)\ **Post date:** [February 15, 2007, 3:59pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/10 "2007-02-15T15:59:46Z")
[QUOTE=Buckwheat] Thank you Captain! So, here is a stupid assumption/joke: nobody would know what year it was during the BC time right? Like a person couldn’t say it was 53 BC because he didn’t know that in 53 more years Jesus would arrive, right? I am just wanting to clarify if I am understanding this correctly. [/QUOTE] Absolutely. As mentioned above, the “BC” designation did not exist until centuries later. Prior to the AD/BC designation, most people refered to dates by such things as “in the 7th year of the reign of King Oxymoron”. ---
**Author:** ![Captain\_Amazing](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@Captain\_Amazing](https://boards.straightdope.com/u/Captain_Amazing)\ **Post date:** [February 15, 2007, 4:09pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/11 "2007-02-15T16:09:43Z")
[QUOTE=Buckwheat] Thank you Captain! So, here is a stupid assumption/joke: nobody would know what year it was during the BC time right? Like a person couldn’t say it was 53 BC because he didn’t know that in 53 more years Jesus would arrive, right? I am just wanting to clarify if I am understanding this correctly. [/QUOTE] Well, right, they wouldn’t say they lived in 53 BC or something. They had other calenders and other ways of dating years. For instance, in the Jewish calendar, today is the 27th day of Shevat in the year 5767. That’s because the Jewish calendar dates from the creation of the world, which, traditionally, Jews believe was 5767 years ago. One of the things the Romans did was to date things “A.U.C”, from the year Rome was founded. So you might see a date that said 500 A.U.C. They might also have used, “In the fifth year of the Emperor Nero”. or, “In the Year that Publius Flaccus and Marcellus Caecellus Metellus were Consuls”. (The Romans elected consuls for a one year period) So, they knew what year it was. They just used a different dating system than the one you’re used to. ---
**Author:** ![Buckwheat](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@Buckwheat](https://boards.straightdope.com/u/Buckwheat)\ **Post date:** [February 15, 2007, 4:21pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/12 "2007-02-15T16:21:54Z")
OK, now my head is starting to hurt. It seems it is more complicated than I thought. HEY Q.E.D. _waves_ 😃 ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [February 15, 2007, 4:25pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/13 "2007-02-15T16:25:15Z")
[QUOTE=FatBaldGuy] SNIP Now it is becoming politically correct to use the terms CE and BCE (Common Era and Before Common Era) to avoid any reference to religion when referring to dates. SNIP [/QUOTE] I once had a devout Christian for a roommate. He preferred CE and BCE because as a detail freak, he hated being 1-5 years off due to that monk miscalculating the actual birthyear of Christ. ---
**Author:** ![FatBaldGuy](https://avatars.discourse-cdn.com/v4/letter/f/ecd19e/32.png) [@FatBaldGuy](https://boards.straightdope.com/u/FatBaldGuy)\ **Post date:** [February 15, 2007, 4:27pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/14 "2007-02-15T16:27:22Z")
[QUOTE=Captain Amazing] For instance, in the Jewish calendar, today is the 27th day of Shevat in the year 5767. That’s because the Jewish calendar dates from the creation of the world, which, traditionally, Jews believe was 5767 years ago. [/QUOTE] Did the Jews actually use this calendar in ancient times, or is it a fairly modern invention? I don’t think that this method of referring to years is ever referenced in the Old Testament. ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [February 15, 2007, 4:29pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/15 "2007-02-15T16:29:18Z")
[QUOTE=FatBaldGuy] Now it is becoming politically correct to use the terms CE and BCE (Common Era and Before Common Era) to avoid any reference to religion when referring to dates. P.S. On preview, it looks like I need to type faster. [/QUOTE] Small nitpik on the idea that using CE and BCE are becoming “politically correct” and that it is a recent event to switch to that usuage- I was taught CE and BCE over 30 years ago in Hebrew School, since it seemed odd to discuss history of the Jewish people, while in synagogue, using direct references to the centrality of Christianity in every day life. So it’s not recent and not just “PC” but represents a fundemental way of viewing the world from a non-Christian point of view. OK then, carry on. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [February 15, 2007, 4:41pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/16 "2007-02-15T16:41:38Z")
Although AUC (_Ad Urbe Condita_, “since the building of the city,” referring to the legendary founding of Rome in 753 BC[E]) is the more famous, probably the most common calendar system in the ancient world (i.e., the last couple of centuries BC) was the [Seleucid Era](http://en.wikipedia.org/wiki/Seleucid_era), which dated things from the accession of Alexander’s general Seleucus I to the throne of an area covering roughly the present Middle East, from Syria into most of Iran. We’re presently in 2319 SE. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [February 15, 2007, 4:44pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/17 "2007-02-15T16:44:48Z")
Interesting detail: There Is No Year Zero. So you go right from 1 B.C. to 1 A.D. (Or 1 B.C.E. to 1 C.E. for you infidel types). If you treat dates like our normal system of numbers you can get an error of one year if your span covers the period assigned to the Birth of Christ, unless you’re careful. And don’t get started on when Christ was really born and how to reconcile the various historical events and the gospels. I don’t want to open that can of worms. ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [February 15, 2007, 4:50pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/18 "2007-02-15T16:50:58Z")
[QUOTE=Polycarp] Although AUC (_Ad Urbe Condita_, “since the building of the city,” referring to the legendary founding of Rome in 753 BC[E]) is the more famous, probably the most common calendar system in the ancient world (i.e., the last couple of centuries BC) was the [Seleucid Era](http://en.wikipedia.org/wiki/Seleucid_era), which dated things from the accession of Alexander’s general Seleucus I to the throne of an area covering roughly the present Middle East, from Syria into most of Iran. We’re presently in 2319 SE. [/QUOTE] _Ab_ is the preposition you want. _Ad_ would be “_to_ the building of the city”, which would be either anachronistic or suggestive of unusual prescience. 😃 ---
**Author:** ![Siam\_Sam](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@Siam\_Sam](https://boards.straightdope.com/u/Siam_Sam)\ **Post date:** [February 15, 2007, 5:02pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/19 "2007-02-15T17:02:44Z")
I was taught that the Greeks started their calendar from 776 BC, the first Olympics. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [February 15, 2007, 5:10pm UTC](https://boards.straightdope.com/t/bc-ad-wtf/392351/20 "2007-02-15T17:10:31Z")
Please allow me to toss in the notion of Julian Date, which was created in the 1500’s to try to avoid all the issues with before and after some arbitrary point in history. It was designed for astronomical usage so that the time between events could be calculated directly without having to cross the border of before and after. For details of this interesting invention, check [this Wikipedia article](http://en.wikipedia.org/wiki/Julian_date) or Google for other treatments. [Next page](https://boards.straightdope.com/t/bc-ad-wtf/392351.md?page=2)