Credit Card Security
Operator: And the issue number...
John: 3
Operator: And could you give me the security code please?
John: [pause] Why?
Operator: That's the last three numbers on the back of the card.
John: That's certainly the answer to the question 'What?', the question I asked however was: 'Wh-y?'.
Operator: It's just for security.
John: Hence no doubt you calling it a security code. But why? Or to put it a very slightly another way: How? How is it for security? I've just given you the number of my card which I've read off my card. Then the expiry date of my card, which I read off my card. Then the issue number of my card, which I read off my card. What I think you and I have proved, working enthusiastically as a team, is that I have my card. So how is reading you another number off my card going to prove anything other than that I still have my card?!?
Operator: Well, it might not be your card. You might have stolen it. You might have stolen someone else's card.
John: I might, true. But how does that impair my ability to read stuff off the back of it!!!
Operator: Well, the thief might not still have your card. What if you gave it to a crooked waiter and he copied down the detail?
John: Well, in that scenario, in which he copies down the details, he would have copied down the details! And one of the details is the security code. I don't pretend to be a criminal psychologist but I find it hard to imagine a criminal waiter who had copied down the 18 digit on one side of the card but then decided copying down the three digit number on the other side is just too much of a fag and he will be fine to bluff it!
Operator: Well, he might not know about the security number.
John: Bless you, that's sweet. Everybody knows about the security number because everyone gets asked for it all the time. The glory days of the security code number as a brilliant Columbo-style-one-last-thing-devastating-surprise-question are quite comprehensively over. So, let me ask you again, why do you want the security code?
Operator: Oh, alright, we're having a raffle in the office and I need a random three digit number.
John: That's all I wanted to know. It's 276.