SCENARIO: PERSON 1 (a scientist) is at the bar in a pub. He orders two drinks and a bag of crisps. He takes these and sits down. He is alone, but clearly waiting for someone. PERSON 2 (a stranger) enters. He sits in the vacant seat at PERSON 1's table, uninvited. The following conversation occurs.

PERSON 1: … hello? Can I help you?

PERSON 2: Did you say you'd just been to Manchester?

PERSON 1: What?

PERSON 2: You just told the barman you've come back from Manchester. I overheard you.

PERSON 1: Oh, right, yeah. I just came back from a conference.

PERSON 2: You mentioned football.

PERSON 1: I did? Oh, yes. It was a nightmare driving back, there was a match on apparently, and the roads were jammed.

PERSON 2: Do you know who the best football team from the Manchester area are?

PERSON 1: Well, I'm not exactly a football fan, but given what I know, it's probably Manchester United.

PERSON 2: Wrong! Open your eyes!

PERSON 1: Sorry, what?

PERSON 2: The best football team in Manchester are the PPs.

PERSON 1: …the what?

PERSON 2: The PPs! It stands for Plough and Potato. It's a pub. They're a brilliant Sunday League side from the Plough and Potato pub, on the outskirts.

PERSON 1: Right. And they're the best team in Manchester?

PERSON 2: Yes. Probably the best in the country.

PERSON 1: Sorry, but I rather doubt that.

PERSON 2: Are you calling me a liar?

PERSON 1: What? No. I'm just saying that, based on the substantial evidence available, what you said is almost certainly wrong.

PERSON 2: So you're saying I'm lying!

PERSON 1: NO! I'm saying you're wrong. They are two different things. You can completely believe what you're saying and still be wrong.