BZ = Before Zero

Short version: it's ridiculous to continue writing historical dates with a system that misses out a year number. To include the year zero, make all BC dates 1 smaller and write BZ (using the US pronunciation bee-zee).

For example, 10 BCE = 9 BZ

Year Zero

In history, especially in ancient history, one has to convert between dating systems now and then. To do that you need a reference scale, a standard, which for most of us is the Common Era (CE), the renamed AD reckoning. It was devised by a learned monk in the sixth century, who estimated a date for the birth of Jesus and used that as the year 1 AD (Anno Domini = Year of our Lord). This is the calendar most of us learned in school, which is now adopted widely around the world, and the one which history books use to pin dates like 378 or 1066 on events. That's fine for the last couple of thousand years, but then you hit a snag. The system as it was applied to dates BC (Before Christ) did not envisage a number zero, which was a mistake.

Zero as a mathematical concept is actually quite advanced, and very few people before the modern era, certainly not historians, were doing tricky stuff like negative numbers. With historically understandable mathematical naivety, therefore, historians became accustomed to the traditional numbering in which 1 BC is the year right before 1 AD.

Mathematicians and astronomers, from Kepler onwards, have merrily included a year zero, because to miss it out would leave an unsightly hole in the number line. All calculations overlapping this hole become needlessly complicated. Nowadays, for example, people doing archaeo-astronomy (working out what dates eclipses and suchlike happened in the past) generally use 'astronomical dating' (NASA). This system aligns with CE dates on all positive years but counts backwards from 0 before that, using negative numbers. Other scientists doing archaeo- stuff, like dendro-chronologists, avoid the problem by using years BP (Before Present), thus reversing direction and sneakily making all past dates positive. But implicitly, in selecting the year that marks the "Present" (1950), they in effect make this year zero in their scale.

I propose that all dates before 1 CE need to be shifted by one year. So 1 BCE will be the new year 0, and dates before this are referred to as BZ (Before Zero).

Now, I'm British and would generally say this as 'bee-zed', but I'd encourage everyone to use the US pronunciation 'bee-zee' instead, because then it sounds quite like the 'bee-cee' we're used to (BC). There is a nice symmetry with After Zero (AZ) as well, which is said 'ay-zee' quite similar to AD, 'ay-dee'. But with CE becoming much the standard for positive dates, and already having an alternate form (AD), I thought introducing yet another synonym for the positive dates might be best avoided.

So, in the years before zero, 2 BCE = 1 BZ, 3 BCE = 2 BZ, and so on. For any BCE date you reduce it by 1, and that's its value BZ.

1 BC becomes Year Zero. We can fix this year with definiteness as (0) the year in which Cossus Cornelius Lentulus Gaetulicus and Lucius Calpurnius Piso were Consuls in Rome, and (1) the year when in China the Han emperor Liu Xin died and Wang Mang was appointed Regent for the new infant emperor.

Impacts

As Fred Espenak puts it (in the NASA link above), Historians should take care to note the numerical difference of one year between 'BCE' dates and astronomical dates.

A final word

The BZ system makes transparent that the proper end of the last millennium was 31st December 1999. The supposed non-existence of a year zero lies behind the tedious argument about such landmark dates that you haven't had a full 2,000 years until the end of the year 2000, when it's turning into 2001. The same with all the centuries, decades and everything. Nothing ending in a 9 counts as the end of anything, because the count started at 1. Which is doing it wrong! If you're timing something, you start the stop-watch at 0. After 59 seconds comes 1 minute, and your time is a whole minute. That's just how timing things works. It's also what we do for birthdays, which are in years. When I'm seven it's because I've spent seven years alive. If you start counting with the clock already at one year, you're just not resetting it properly. Of course there was a year zero. When that year was up, the Common Era had its first birthday, and year 1 began.