The trouble with Scotland is that it's full of Scots
I always chuckle at that when Edward Longshanks says it in Braveheart. I love Scotland and the Scots though.
Oh yeah, this is about evidence that makes the Bible Flood non factual. While you'll never 'win' an argument with a true believer, it can plant seeds that germinate later. Present the facts, allow the facts to speak for themselves. Even if they don't accept them from you, you evil apostate, they may later stumble onto similar info from another source not as likely to trigger the defense mechanism.