For other uses see Millennium (disambiguation). Lists of miscellaneous information should be avoided. Please relocate any relevant information into appropriate sections or articles. (November 2010)

A millennium (plural millenniums or millennia)1 is a period of time equal to one thousand years (1000)from the Latin phrase mille thousand and annus yearoften but not necessarily related numerically to a particular dating system.

For example a millennium could start at the beginning of the year 289 and finish at the beginning of the year 1289.

Sometimes it is used specifically for periods of one thousand years that begin at the starting point (initial reference point) of the calendar in consideration (typically the year "1") or in later years which are whole number multiples of a thousand years after it. The term can also refer to an interval of time beginning on any date. Frequently in the latter case (and sometimes also in the former) it may have religious or theological implications (see millenarianism). Sometimes in religious usages such an interval called a "millennium" might be interpreted less precisely i.e. not always being exactly 1000 years long. Contents 1 Counting years 1.1 Ordinal 1.2 Ranges 2 Debate over millennium celebrations 2.1 Arbitrariness of the selection of the Year One 2.2 Viewpoint 1: x001y000 2.3 Viewpoint 2: x000x999 2.4 Popular approach 2.5 Commentary on "The Millennium" 3 See also 4 References 5 External links Counting years Ordinal

The original method of counting years was ordinalcitation needed whether 1st year A.D. or regnal 10th year of King Henry VIII. This ordinal numbering is still present in the names of the millennia and centuries for example 1st Millennium or the 20th century and sometimes in the names of decades e.g. 1st decade of the 21st century. Ranges

A change from ordinals to cardinals is incomplete and might not ever be completed; the main issues arise from the content of the various year ranges. Similar issues affect the contents of centuries. Decades are usually referred to by their leading numbers and are therefore immune to this controversy: the decade called 1990s would by its naming not include 2000. Similarly the 100 years comprising the 1900s share 99 years in common with the 20th century but do not include 2000.

Those following ordinal year names naturally choose 20012100 as the current century 20013000 as the current millennium

Those following cardinal year names equally naturally choose 20002099 as the current century 20002999 as the current millennium Debate over millennium celebrations

The common Western calendar i.e. the Gregorian calendar has been defined with counting origin 1. Thus each period of 1000 years concludes with a year number with three zeroes e.g. the first thousand years in the Western calendar included the year 1000. However there are two viewpoints about how millennia should be thought of in practice one which relies on the formal operation of the calendar and one which appeals to other notions that attract popular sentiment. A number of countries have legally adopted ISO 8601 also used in other contexts which uses the astronomical calendar in which year counting starts at 0. Thus when using this calendar the millennium starts at x000 and ends at x999. There was a popular debate leading up to the celebrations of the year 2000 as to whether the beginning of that year should be understood (and celebrated) as the beginning of a new millennium. Historically there has been debate around the turn of previous decades centuries and millennia. The issue is tied to the convention of using ordinal numbers to count millennia (as in "the third millennium") as opposed to using cardinal numbers (as in "the two thousands") which is unambiguous as it does not depend on which year counting starts. The first convention is common in English speaking countries but the latter is favored in for example Sweden ("tvtusentalet"). Arbitrariness of the selection of the Year One Main article: Anno Domini

As a side-note to the debate on timing of the "turning of the millennium" the arbitrariness of the era itself can be raised. Mathematically the choice of the zero point on any timeline is an arbitrary one. (However once chosen it must be abided.) The Gregorian calendar is a secularized de facto standard based on a significant Christian event the purported date of the birth of Jesus Christ. Thus the foundation of the calendar may not be as relevant to non-Christians. The calendar is one among many other calendars that are still in use and have been used historically. Adjustments and errors in the calendar (such as Dionysius Exiguus's incorrect calculation of the year 1 AD) make the particular dates we use today arbitrary. However everyone can utilize the current very common calendar referring to its years as either being year of the "Christian Era" or the "Common Era" or the years earlier than this one as being either before the "Christian Era" or before the "Common Era" abbreviated BCE.. Viewpoint 1: x001y000 Those holding that the arrival of new millennium should be celebrated in the transition from 2000 to 2001 (i.e. December 31 2000) argued that since the Gregorian Calendar has no year zero the millennia should be counted from 1 AD. Thus the first period of one thousand complete years runs from the beginning of 1 AD to the end of 1000 AD and the beginning of the second millennium took place at the beginning of 1001. The second millennium thus ends at the end of the year 2000. Then again those who defend the opposite idea state that the new millennium started with the year 2000 (because of the changes made to the Gregorian calendar in 1582 or because the first millennium started in 1 AD. and ended in 999 AD being the only millennium (along with the last millennium b.c.) not with 1000 years but with 999 years). Illustration of years with a 0001 demarcation 2 BC 1 BC 1 AD 2 3 4 5 ... 998 999 1000 1001 1002 1003 ... 1998 1999 2000 2001 2002 2003 ... 2998 2999 3000 3001 3002 3003 First one thousand years (millennium) Second millennium Third millennium Fourth millennium Arthur C. Clarke gave this analogy (from a statement received by Reuters): "If the scale on your grocer's weighing machine began at 1 instead of 0 would you be happy when he claimed he'd sold you 10 kg of tea" This statement illustrates the common confusion about the calendar. If one counts from the beginning of AD 1 to the ending of AD 1000 one would have counted 1000 years. The next 1000 years (millennium) would begin on the first day of 1001. So the calendar has not 'cheated' anyone out of a year. Clarke made reference to this viewpoint in his book 3001: The Final Odyssey referring to the Millennium Celebrations on January 31st 2000. In other words the argument is based on the fact that the last year of the first two thousand years in the Gregorian Calendar was 2000 not 1999. Viewpoint 2: x000x999 The "year 2000" has also been a popular phrase referring to an often utopian future or a year when stories in such a future were set adding to its cultural significance. There was also media and public interest in the Y2K bug. Thus the populist argument was that the new millennium should begin when the zeroes "rolled over" to 2000 i.e. the day after December 31 1999. Peoplewho felt that the change of hundred digit in the year number and the zeros rolling over created a sense that a new century had begun. This is similar to the common demarcation of decades by their most significant digits e.g. naming the period 1980 to 1989 as the 1980s or "the eighties". Similarly it would be valid to celebrate the year 2000 as a cultural event in its own right and name the period 2000 to 2999 as "the 2000s". Most historians agree that Dionysius nominated Christ's birth as December 25 of the year before AD 1.2 This corresponded with the belief that the birth year itself was considered too holy to mention.citation needed It also corresponds to the notion that AD 1 was "the first year of his life" as distinguished from being the year after his first birthday. Similarly in 1000 AD the churchwhich actively discouraged any mention of that year and in modern times itwhich labelled 2000 AD as the "Jubilee Year 2000" marking the 2000th anniversary of the birth of Christ.citation needed The AD system counts years with origin 1. Somewho assume a preceding Year 0 for the start of the first Christian millennium in order to start the millennia in year numbers multiple of 1000. Illustration of years with a 9900 demarcation using 0 (ISO 8601 and astronomical numbering system) 1 AD  0   1   2   3   4   5   ...   998   999  1000 1001 1002 ... 1998 1999 2000 2001 2002 ... 2998 2999 3000 3001 3002 First millennium (1000 years) Second millennium Third millennium Illustration of years with a 9900 demarcation (starting AD 1) 1 BC 1 AD  2   3   4   5   ...   998   999  1000 1001 1002 ... 1998 1999 2000 2001 2002 ... 2998 2999 3000 3001 3002 First millennium (999 years only) Second millennium Third millennium Popular approach The majoritycitation needed popular approach was to treat the end of 1999 as the end of a millennium and to hold millennium celebrations at midnight between December 31 1999 and January 1 2000 as per viewpoint 2. The cultural and psychological significance of the events listed above combined to cause celebrations to be observed one year earlier than the formal Gregorian date. This does not of course establish that insistence on the formal Gregorian date is "incorrect" though some view it as pedantic (as in the comment of Douglas Adams mentioned below). Some event organisers hedged their bets by calling their 1999 celebrations things like "Click" referring to the odometer-like rolling over of the nines to zeros. A second approach was to adopt two different views on the millennium problem and celebrate the new millennium twice. Commentary on "The Millennium" Stephen Jay Gould noted in his essay Dousing Diminutive Dennis' Debate (or DDDD 2000) (Dinosaur in a Haystack) that celebrations and media announcements marked the turn into the twentieth century along the boundary of 1900 and 1901 citing among other examples the New York Times's headline "Twentieth Century's Triumphant Entry" on January 1 1901. Gould also included comments on adjustments to the calendar such as those by Dionysius Exiguus (the eponymous "Diminutive Dennis") the timing of celebrations over different transitional periods and the "high" versus "pop" culture interpretation of the transition. Further of his essays on this topic are collected in Questioning the Millennium: A Rationalist's Guide to a Precisely Arbitrary Countdown. In the editorial to 2002's Best American Essays Gould highlights the use of historical events rather than transitional dates to delineate periods of history: "Many commentators have stated quite correctly in my view that the twentieth century did not truly begin in 1900 or 1901 by any standard of historical continuity but rather at the end of World War I the great shatterer of illusions about progress and human betterment... I suspect that future chroniclers will date the inception of the third millennium from September 11 2001." Douglas Adams highlighted the sentiment that those in favor of a 2001 celebration were pedantic spoil-sports in his short Internet article Significant Events of the Millennium. This sentiment was also demonstrated when in 1997 the Australian Prime Minister John Howard made a point in favor of the celebration's being in 2001 and he was named "the party pooper of the century" by local newspapers. In an episode of the American television series Seinfeld titled "The Millennium" Jerry Seinfeld states "Since there was no year zero the millennium doesn't begin until the year two-thousand and one."3 In the TV series The X-Files there is an episode titled "Millennium" continuing the TV series of the same name. In this episode Dr. Scully mentions that the new Millennium doesn't start until January 1 2001. She is made fun of but not suggested to be incorrect. Mulder responds "No one likes a math geek Scully." The action of the book The Headless Bust: A Melancholy Meditation on the False Millennium by Edward Gorey takes place on December 31 1999 and it refers to the next coming year as the start of the new Millennium despite the fact that the title of the book calls it the "False Millennium." The host of the game show Jeopardy! Alex Trebek proudly welcomed his guests and the contestants to the "first day of the 21st century" on January 1 2001. The science writer Sir Arthur C. Clarke firmly stated in his writings that the beginning of the New Millennium would be on January 1 2001. Clarke had also very optimistically prophesied that on that date all telephone calls worldwide would become local calls. In other words there would no longer be any extra charges for long-distance calls anywhere. Linguist Arnold Zwicky suggested an analogy with the adjustment from Julian to Gregorian calendar:4 Let's take a clue from the defective Gregorian year the one with only 355 days in it. ... If a year can be stipulated to be defective by some days why can't a decade century or millennium be stipulated to be defective by a year Why don't we just say that the first decade in our western calendar was short by a year Then as a result the first century was similarly short and the first millennium too. Thereafter nothing's defective. This stipulation performs a cultural function; it aligns the beginning of every decade century and millennium (except the very first of each of these) with an auspiciously numbered year. See also List of calendars Decade Century Millennialism Millennium bug Millennium Dome Millenarianism Third millennium White House Millennium Council Y2K References Millennia is the Latin plural form but both are used in English.Dictionary.com History Today June 1999 p60 Letters Darian Hiles: "Of Dates and Decimals" Seinfeld script: The Millennium Zwicky Arnold M.. "Millennial matters". Stanford University. http://www.stanford.edu/zwicky/calendar.Comrie.pdf. 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