How the hell does someone seriously believe the earth is 6000 years old?
Meh. It baffles me.
My belief:
We are belief-run creatures. It is simply a matter of what information reaches a developing brain first: fact or fiction. Once beliefs are set in stone at an early age, they are very difficult to remove, and no amount of logic or actual real-world empirical truth can budge them, because they become a part of the identity structure, and once that happens, its all over. This is especially true with religious beliefs, because they inform identity and perform a social purpose (church). With so many important functions being serviced by such identity and core-beliefs, they become impossible to remove unless through something traumatic. It is tragic that we are so susceptible to our own minds, and capable of being so oblivious to the world around, but such is the way it was throughout our evolution. There was no incentive to be scientific, because there was no science yet until only recently. The only incentive we had was to learn to get along with eachother in our hunter-gather group, in other words: to cooperate. This was the ultimate end, and so beliefs that facilitate this are rewarded. This includes the unifying function of spiritual beliefs, which brought people together on a deep level, easily, regardless of whether those beliefs corresponded with the physical reality and history of the universe. So, this is where we are today. Run by false beliefs, and defending them to the death. Beliefs and our affinity for them cause all of the problems we have as humans. If we were simply more humble, and not so convinced of our own righteousness in terms of religion and politics, we could all get along a lot better.
I think that within the mind of a person holding young earth creation beliefs, they think that following a literal interpretation of the bible will score them points with Jesus, basically. It is a test of faith to not question anything, or take a less literal interpretation of the book. They think therefore, that they will be 'preferred' over other Christians who do not hold such a literal view.