| We control what |
you think with
 Anno Domini and Before Christ
The use of A.D. originally came about during the 5th century C.E., when a Christian monk called Dionysius Exiguus wanted to record and predict religious holidays such as Easter. Historians of the time had followed a variety of previous dating schemes, including the dominant Roman one of "A.U.C." ("Ab Urbe Condita" or "After the Founding of the City") or a shorthand method that simply named the reigning consuls of that year. In Exiguus' time, the dominant system was Anno Diocletiani - years since the beginning of the reign of the Emperor Diocletian. But Exiguus did not like that, since Diocletian launched one of the greatest persecutions of Christians in history.
As Christianity became increasingly dominant, it eventually began to encompass almost the whole of the literate community in Europe, with religious communities becoming the main bastions of histories during the Middle Ages. It is no surprise, then, that they began to use the same method of dating for both their religious timekeeping and secular events. All years began to be designated A.D. for the most part, with various local varieties of B.C. - including the clumsy A.V.I.D.T. ("Ante Vero Incarnationis Dominicae Tempus" or "the Time Before the Lord's True Incarnation"). Alternate local methods largely dropped away.
There are several arguments against the usage of the Common Era system. Pretty much all are from conservative Christians stating that the removal of AD and BC is "oppression" of their religion — as if enforcement of AD and BC isn't oppression of anyone else's religion or religious calendar.
Another argument is an appeal to plain honesty — that since everyone knows what the epoch is really about, it is a hollow token gesture, serving no purpose beyond political correctness, to alter the labels.
Support for the BC/AD system over BCE/CE due to the fact that it is based around the birth of Jesus is strange, considering that AD and BC are almost certainly inaccurate themselves. The birthdate of Jesus was definitely not in 1 AD. He was probably born in 4 BC (and most certainly not December 25th). Therefore, since the BCE/CE is technically an arbitrary date, which is set due to the historical precedent of AD/BC in the Gregorian calendar, and doesn't shift, it will always remain accurate.
Another criticism of the Common Era system is that it leaves much of history in BCE dates, and for added confusion lacks a year zero. There have been several suggestions to pick an earlier starting point, which would enable a single system to address all of history. Joseph Scaliger proposed Julian Era dates, from 4713 BCE. Another proposal, by Cesare Emiliani, is the Holocene Era, with an epoch of 10,000 BCE. This has the advantage that the arithmetic for conversion is far more straightforward than Julian Era: 2013 CE = 12013 HE.
On a practical level BCE/CE really doesn't do its job very well. Is the text actually referring to 30CE or was a "B" lost at some stage? On the other hand, it's quite hard to come up with a typo that could substitute AD for BC.
- ↑ Dictionary.com definition
- ↑ Merriam Webster definition
- ↑ http://hbar.phys.msu.ru/gorm/chrono/paschata.htm
- ↑ Although some people do try to claim America is a Christian nation by noting the use of "the year of our Lord" in the preamble to the U.S. Constitution.
- ↑ When was Jesus born? Was Jesus born on December 25 — Christmas Day?
- ↑ As for year zero, there is a year zero defined by ISO and astronomers also use a year zero for calculating purposes. In both cases year zero takes the place of 1 BC or 1 BCE so that the dates before that are shifted back. Historians never use a year zero, so people will have to deal with that. In any case, a year is an interval, not a point. This means that the historical lack of year zero is perfectly logical. The year 2 AD/CE began after a year (year 1 AD/CE) had elapsed from the original point of departure.