Two nuns go out of the convent to sell cookies. One of them is known as Sister Mathematical (SM) and the other one is known as Sister Logical (SL). It is getting dark and they are still far away from the convent.

SL: Have you noticed that a man has been following us for the past half-hour?

SM: Yes, I wonder what he wants.

SL: It's logical. He wants to rape us.

SM: Oh, no! At this rate he will reach us in 15 minutes at the most. What can we do?

SL: The only logical thing to do of course is to start walking faster.

SM: It is not working.

SL: Of course it is not working. The man did the only obvious thing to do. He started to walk faster too.

SM: So, what shall we do? At this rate he will reach us in one minute.

SL: The only logical thing we can do is split. You go that way and I'll go this way. He cannot follow both of us. So they split up and the man decided to go after Sister Logical. Sister Mathematical arrives at the convent and is worried because Sister Logical has not yet arrived. Finally, Sister Logical arrives.

SM: Sister Logical! Thank God you are here! Tell us what happened!

SL: The only logical thing happened. The man could not follow both of us, so he followed me.

SM: So, what happened? Please tell us.

SL: The only logical thing to happen. I started to run as fast as I could.

SM: So what happened?

SL: The only logical thing to happen. The man also started to run as fast as he could.

SM: And what else?

SL: The only logical thing to happen. He reached me.

SM: Oh, no! What did you do then?

SL: The only logical thing to do. I lifted my dress up.

SM: Oh, Sister. What did the man do?

SL: The only logical thing to do. He pulled down his pants.

SM: Oh, no! What happened then?

SL: Isn't it logical, Sister? A nun with her dress up can run faster than a man with his pants down...