rmwilliamsjr said:
It is not a presupposition, it is a conclusion.
Look at the history of the formation (of the scientific principle) of geological ages, it was dominated by Christians who did NOT want to see long ages but wanted to find geological evidence for a young earth. Essentially they went looking for evidence of the Noahic flood and found an old earth.

You are mistaken here, what you are actually talking about is theory. These people may have been sincere in the conclusions that they found, but that doesn't mean that the conclusions were correct.
YE scientists such as those at answersingenesis.org have come to the conclusion based on the same facts, that the Earth in indeed young.
These YE scientists however, are willing to admit where fact and theory end. Choosing instead to let Scripture be their guide. As someone at Answers In Genesis said, they have yet to see one fact conflict with the YE view (not exact quote).
If you have, something specific in mind that you disagree with the findings of YE scientists, please by all means post it.