If the worst anybody can do is say "we don't really know anything" and bash my degree as if its something bad then I'm not particularly impressed. And for the record I was originally giving my opinion as to why the 4000 BC start date was probably not influenced by the religious right. However I saw it necessary to respond to a lot of bunk directed at me for a sentence i tacked on the end of one of my initial posts. In the end after much goading I had to actually present reasons that civilization couldn't have begun around 2000 BC. Its not so much proving that the earth is 4.5 billion years old that has been raised here but proving that it is not 6000 years old and not completely flooded 4000 years ago. This is about as easy as proving that tigers are not purple.
I thought you said you grew up in a Christian home. I would have thought you've heard all the counter-arguments to what you have put up to the plate (considering your degree in history). But, just in case you haven't, allow me to explain why the "scientific" way of explaining the universe is, yes, just like any other religion.
Let's begin with your literal translation of the Christian Bible. It is debated in the Christian world that many stories are not to be taken literally. For instance, the story of Adam and Eve. Taken literally, the Bible states that humanity began with one man and one woman and from that all other humans originated. However, it is debated that "Adam" could mean men and "Eve" could mean women-meaning that in the beginning of the world God created man and woman (not just one of each but many). This can be applied to many other scriptures such as the story of Noah. Taken literally, the Bible states that from 8 people all modern civilizations originate. However, it is debated that those 8 people could stand for 8 tribes, etc.. I would have thought you would have known this since you have that almighty degree in history.
However, lets say that the Christian Bible should be taken literally and that all modern life did truly come from 8 people. Who's to say that God did not then create the indigenous people of Australia or the Americas? If there is a God then he is all-powerful correct? Then why is it so hard to believe that God did not recreate animal and plant life? Is this so hard to fathom? Why then are religious people marked as nut-jobs? And by the by, the Bible does not state the true age of the Earth. So, just like any other belief system (including atheism) the Christians do not KNOW beyond the shadow of a doubt that they are correct.
In regards to carbon dating, there is no way of us to know that the system works 100%. I'm not trying to be foolish, however. I am sure that this method of dating has been tested on things we do know the age of. I am sure that scientist don't just take wild guesses about the age of things such as the globe. Then again, neither do religious people. We may discover in 10 years that carbon dating gives false results and that (for some chemical reason) it does not work for something over 1000 years old. Carbon dating is just as reliable as the Bible, Torah, Qu'ran or any other religious text.
You are correct, no one alive today was alive in 1880 AD. Does that mean that we have no idea of what occurred at that time? Of course not. We can have some idea of what occurred in that time period. However, we do not know for sure. History is written by the victor, I'm sure you learned that in history class. Why then when someone analyzes that time period in a different way than you they are classified as zealots? (And I thought religious people were the intolerant ones.)
There is no evidence in existence to prove 100% where we came from. Perhaps civilization on Earth has existed for millions of years but every time civilization builds itself up, it destroys itself again. Maybe aliens lived on Mars until the planet was hit by and asteroid after which they fled to Earth. Maybe we are all just figments of a larger beings imagination and when it wakes up we all will cease to exist. Maybe the "Big Bang" theory is correct and we have evolved over thousands of years from single-celled organisms into the people were are today. And maybe there was a God who created man thousands of years ago. No one knows. So no one has the right to say another persons theory is wrong. They can bring up points to show why they feel they are right or try and convince others of such, but they have no right to say that they know 100% that the are correct and the others are wrong.
Remember, I'm not talking about the little science experiments you did in college where you proved what paper towel roll can soak up the most moisture. I am talking about the "scientific" theories which NO ONE can prove. The theories that are JUST LIKE any theory brought up by a religion. Both of which are gathered from an assumption of what occurred in the past and by evidence seen today. I am not trying to say that any one theory is wrong or right. All I am saying is: Who are you to say that you know for a fact that all creationists are incorrect?
When the crap hits the fan, atheists are just like any other religious person. Just like a Christian, Muslim, Buddhist, Hindi, or Jew will defend their "evidence" to their last breath, any atheist would do the same. The only thing that bothers me is that atheists claim that they are above religion. That they do not need a crutch to hold them up in life. Well, I'm sorry to be the one to point this out to you, but you have a crutch to, in scientific THEORIES. Every person has basic needs. Water, food, social interaction, and a spiritual need. Yes, every person. No one is above it. Religious people choose to fill that need with a religion of their choice. (Involving a God or other creationist ideas) Atheists choose to fill that need with scientific theories. Theories that CAN NOT be proven true just like any other religion. WE ALL have to have FAITH in whatever it is we believe to be true. No one can prove anything beyond a shadow of a doubt. No one is above having faith in what they believe to be true. (Even if they have a college degree.)