Here's how a recent fictional conversation with Bill Maher went.
Bill Maher: If Christianity is true, show me proof!
Me: Bill, let's skip over the opening fluff and get to the heart of the issue. This is how this conversation is likely to go:
I'm going to present the Bible as proof of a historical record of eye witness accounts.
You're going to say that the Bible isn't reliable and that its claims are not true.
I'm going to say, "Great you believe in truth" and then ask you what truth is according to your worldview and how you can know truth without revelation from God.
You're going to say that truth is what corresponds to reality and that you only go by conclusions derived from scientific discovery.
I'm going to say that since all science is dependent on the inductive principle and that the inductive principle requires many preconditions which must first be accepted as true, the scientific method alone cannot account for what is true. The reliability of the principle of induction requires a number of precomitments. That there is a past, that the past isn't an alternate reality being fed to us, that our cognitive facilities are reliable to make sense of the past, and that the way things have worked in the past will continue to be a reliable indicator of how things will work in the future.
We must then ask ourselves on what basis do we determine if these precommitments are valid? We cannot prove them scientifically, because to attempt to do so would be to argue in a circle since the scientific method itself depends on these precommitments.
Since you're a sharp guy and you know this already, you're going to say you simply assume the reliability of the inductive principle.
At which point I'm going to point out that "assumption" is taking something to be true without evidence, which contradicts what you said earlier about how you arrive at knowledge of the truth.
You're going to respond by saying that everyone's worldview has to start by making these assumptions.
I'm going to say according to my worldview, these truths are revealed to us by divine revelation, so we can know they are reliable. Then I'm going to ask you how you can know about what other people's worldviews are founded on, if you can't account for truth even according to your own worldview?
You're going to act incredulous and claim that you did receive revelation that induction is reliable from a flying spaghetti monster in the sky.
I'm going to point out that this discussion started with me arguing on the basis of eye witness accounts recorded in scripture, and ended with you arguing for the existence of a flying spaghetti monster.
(Bill is quiet).
Bill, I'm going to ask you to consider that your worldview takes you to absurdity. I want you to hear the truth of the Gospel that God might open your eyes to the truth.
Answer not a fool according to his folly,
lest you be like him yourself.
Answer a fool according to his folly,
lest he be wise in his own eyes.
What started with eyewitness accounts, ended with you arguing for the Flying Spaghetti Monster.—Jordan Wilson