The two men responsible for the 6,000 year old earth idea were John Lightfoot and James Ussher. If you're even willing to consider looking at it, you can just google Ussher and it will include Lightfoot. The idea that just because someone is a creationist, they automatically believe in the Young Earth is wrong. Yes, some creationists do believe that chronology but the evidence in geology and physics does not support it. The Bible itself gives no indication of when creation occurred although, I believe someone mentioned that the Bible indicates the Earth is very old. At least God is referred to as "The Ancient of Days." Sounds like more than 6,000 years to me.
Why would you suppose that any of this is news to me, any more than the established fact that numerous Christians accept evolution is news to me? The person I am arguing against, mlc9852 *is* a young earth creationist, along with most creationists on these threads. Hence the thrust of my remarks. Speaking personally I believe that old earth creationist are wrong, but I don't think that they are witlessly wrong as YEC are, and I wouldn't deride OEC for their beliefs. If you/they want to believe that God tinkers with DNA over billions of years then that belief is not science (IMHO) but it is also not stupid. Hope you don't find that patronising. Just explaining where I am coming from.