Just what does this have to do with the millennium? It is the reason why we have no year zero. As we said, Dionysius did not have the benefit of dubbing Christ's birth year as zero, since the numeral had not been invented yet. Even when the AD system was popularized by a monk named Venerable Bede in the 8th Century, who also created and used the BC system, zero was not used as a starting point for counting things. Even after the BC system came into popular use, during the Renaissance, people would never have thought of dubbing any year strictly as Year Zero.
Even when our current calendar was developed, and all the way up to today, we don't always use zero as the starting point in our counting, since it is used to represent naught, or nothing. January is the first month of the year. Each month starts with one, and not zero. We use numbers in this sense to represent a product, in this case, a set amount of time (days, months, years) that has, is, and will pass. It is assigning something tangible to things that are intangible. A child's first year of life is still referred to as "Year 1" of that child's exsistence, even though the child is not yet a full year old.
The simplist example of why counting systems, when used in this manner, cannot start with zero is our monetary system. Gather together 10 one dollar bills, and start counting. We start with one, otherwise we will only get to nine if we start with zero. Which is why we don't start with zero -- the bill that zero would represent does not exist. Since it does not exist, we have no need to include it in our calculation. So, we start with 1. For the most part, zero is the only number that is not used regularly in our methods of counting, and still is used primarily as a means to have an infinity of number calculations, without having an overwhelming amount of symbols to represent those numbers. |