I don't know why, but sometimes people ask me if I'm Scottish (big black American guy with no discernable foreign accent). So, sometimes I answer, "Yes, I am."

Then they say, "You can't be Scottish!" To which I drone as dryly as possible, "My original family name is Ramsey, an Anglicisation of Ramsay of the Dalhousie Ramsays. Our clan leader is the Earl of Dalhousie at Brechin Castle in Angus, Scotland. Our family emblem is the unicorn and our family motto is 'Ora et Laborum' meaning 'Pray and Work'."

Halfway though my speach, their eyes have glazed over they're very sorry they brought it up.

In fact, my latest victim of the "Are you Scottish? You can't be Scottish!" monologue was at a housewarming party for one of my wife's co-workers.

The victim was a black woman who was English. After my speach, I added, "Seems I'm as Scottish as you are English."

She didn't come near me for the rest of the evening.

If you can't blind them with brilliance or baffle them with b.s., then bore them to tears with details.