[Mittelwaechter]

True for red french cows with a winking eye.

Let's assume I show you three white hats and two red hats.
There are three chairs in a row, one behind the other. Two of your friends have a seat behind you while you sit on the first chair.
I put everyone of you a hat on, but you can't see its colour. No one is allowed to turn his head or touch his hat. Keep your face forward, don't move.

Everyone sees the hat/s of the one/s in front of him, but not his own or the hats behind him. You see nothing.
I ask both of your friends what the colours of their hats are, but they could not tell me.
So I ask you - on the first chair:
Please explain to me, how you know the colour of your hat? No one tells you.