A New Decade? Bah Humbug!
It happens at the end of every decade—or at least at what a lot of people think is the end of a decade. More specifically, it happens at the end of every year that ends in “9.” And so it is that at the end of 2019 we are again bombarded with announcements in the news media and elsewhere that we are about to enter another decade with the beginning of 2020. Although not as hyped as the celebrations of twenty years ago when millions anticipated that we were entering a new century and millennium with the beginning of year 2000, it is certainly a matter of public consciousness, and will be every ten years.
But is the first day of 2020 in fact the beginning of another decade on the calendar? All celebrations aside, for those who wish to get an answer that is historically and mathematically accurate it is a matter of consulting the author of the modern western, or Christian dating system that is used by most of the world today. First of all, however, we should not overlook the obvious: Any period of ten years—beginning on any date in any year—may be recognized as a “decade” for private, organizational, or corporate use. But even with that in mind, is the popular conception of the decade correct—that 31 December 2019 is the final day of the 2010s decade, and that 1 January 2020 is the first day of the 2020s decade?
Unfortunately for the popular conception, the answer is “No.” That is because the proper beginning of any decade is the first day of the year ending in “1.” Conversely, the final day of a decade is 31 December of the year ending in “0.” Some will object that 2020 must be the beginning of another decade because “that is when the big numbers change”—much like those who were insisting twenty years ago that 1 January 2000 was to be the beginning of another century and millennium. In both cases the popular conception is a year too early. And that is not because I say so, but because that is what we deduce from the writings of the creator(s) of this dating system.
Thanks to the more widespread discussions of these matters twenty years ago, it is now fairly common knowledge that the modern western/Christian dating system is a somewhat indirect result of the creation of a Paschal (Easter) calendar by a monk named Dionysius Exiguus in the early sixth century. Writing in the year he identified as AD 525, his schedule of dates for the Easter celebration covered the upcoming years 532-626. In the course of his explanation in the accompanying documents, he suggested to the Pope and his officials that they begin to date themselves by the birth of Jesus Christ—by “Anno Domini” or, “Year of the Lord,” rather than dates connected with any human system of government such as the Romans.[1]
The other “creator” of this dating system was the Venerable Bede, who lived two centuries after Dionysius. In about AD 725 his Ecclesiastical History of the English People extended the dates of Dionysius backward to include those years recognized as “BC” (Before Christ), or “AC” (Ante Christum). From the calculations of Dionysius and Bede, therefore, the apparent date of Jesus’ birth is 25 December 1 BC. Seven days later is 1 January AD 1, with no year “0” in between. While many have surmised and stated that Dionysius was at least a couple years off in his calculation of the year of Jesus’ birth, including myself, that date is nevertheless the basis for the modern western/Christian dating system. Consequently, it can be stated confidently that the proper beginning for any decade within this system is 1 January of the year ending in “1.”
Regardless, this will not put an end to the popular understanding, and there is thankfully no real penalty or consequence for the infraction other than the occasional reminder from a few chronologers and theologians. And the more urgent chronological matter of the coming decade will surely be the calculations of some concerning the 2000th anniversary of Jesus’ crucifixion and resurrection in 2033.
[1] Steven L. Ware, When Was Jesus Really Born: Early Christianity, the Calendar, and the Life of Jesus (Saint Louis: Concordia, 2013), chapter five.
But is the first day of 2020 in fact the beginning of another decade on the calendar? All celebrations aside, for those who wish to get an answer that is historically and mathematically accurate it is a matter of consulting the author of the modern western, or Christian dating system that is used by most of the world today. First of all, however, we should not overlook the obvious: Any period of ten years—beginning on any date in any year—may be recognized as a “decade” for private, organizational, or corporate use. But even with that in mind, is the popular conception of the decade correct—that 31 December 2019 is the final day of the 2010s decade, and that 1 January 2020 is the first day of the 2020s decade?
Unfortunately for the popular conception, the answer is “No.” That is because the proper beginning of any decade is the first day of the year ending in “1.” Conversely, the final day of a decade is 31 December of the year ending in “0.” Some will object that 2020 must be the beginning of another decade because “that is when the big numbers change”—much like those who were insisting twenty years ago that 1 January 2000 was to be the beginning of another century and millennium. In both cases the popular conception is a year too early. And that is not because I say so, but because that is what we deduce from the writings of the creator(s) of this dating system.
Thanks to the more widespread discussions of these matters twenty years ago, it is now fairly common knowledge that the modern western/Christian dating system is a somewhat indirect result of the creation of a Paschal (Easter) calendar by a monk named Dionysius Exiguus in the early sixth century. Writing in the year he identified as AD 525, his schedule of dates for the Easter celebration covered the upcoming years 532-626. In the course of his explanation in the accompanying documents, he suggested to the Pope and his officials that they begin to date themselves by the birth of Jesus Christ—by “Anno Domini” or, “Year of the Lord,” rather than dates connected with any human system of government such as the Romans.[1]
The other “creator” of this dating system was the Venerable Bede, who lived two centuries after Dionysius. In about AD 725 his Ecclesiastical History of the English People extended the dates of Dionysius backward to include those years recognized as “BC” (Before Christ), or “AC” (Ante Christum). From the calculations of Dionysius and Bede, therefore, the apparent date of Jesus’ birth is 25 December 1 BC. Seven days later is 1 January AD 1, with no year “0” in between. While many have surmised and stated that Dionysius was at least a couple years off in his calculation of the year of Jesus’ birth, including myself, that date is nevertheless the basis for the modern western/Christian dating system. Consequently, it can be stated confidently that the proper beginning for any decade within this system is 1 January of the year ending in “1.”
Regardless, this will not put an end to the popular understanding, and there is thankfully no real penalty or consequence for the infraction other than the occasional reminder from a few chronologers and theologians. And the more urgent chronological matter of the coming decade will surely be the calculations of some concerning the 2000th anniversary of Jesus’ crucifixion and resurrection in 2033.
[1] Steven L. Ware, When Was Jesus Really Born: Early Christianity, the Calendar, and the Life of Jesus (Saint Louis: Concordia, 2013), chapter five.