*bj0rn: what i mean by mathematical and logical:*

we DO begin counting with ‘0’, so we havent finished ‘1’ until we say ‘1’!

I’m not really sure what you’re saying here. When I start counting, I start with 1. I never say “0” when counting.

*example: you havent lived one year of your life until you become 1 years old! if you would start counting on ‘1’ you would be born 1 years old and become 2 years old after 1 year.*

You’re confusing cardinal numbers (age) with ordinal numbers (first, second, third, etc.).

E.g.:

The 1[sup]st[/sup] year of my life, I was 0 years old (10/28/64 - 10/27/65)

The 2[sup]nd[/sup] year of my life, I was 1 year old (10/28/65 - 10/27/66)

The age numbers indicate how many *full* years I’ve lived.

Part of the confusion is that our year numbering is actually ordinal. Right now we are in the 1999[sup]th[/sup] year AD. But since 12:00 Midnight January 1, 1 AD, the world has experience 1,998 years,

10 months (though we’re in the 11[sup]th[/sup]),

29 days (though we’re in the 30[sup]th[/sup]),

9 hours (this matches the time because time is measured cardinally),

and an odd number of minutes.

*… because a man born 1 bc should be 2 years old in the year 1 ad, not 1 years old as it is in history.*

Au contraire. If I was born 10/28 in 1 BC, I would turn 1 year old on 10/28/1 AD. There are only 365 days between these two days, not 730.

Even though we’re tempted to express 1 BC as -1, this is mathematically incorrect, because year numbers are ordinal. Remember there was no 0 AD or 0 BC. (0th year?) 1 BC ended 12/31/1 BC. The next day was 1/1/1 AD.