Every week I go to Woolworths to do the grocery shopping. Most weeks I wander up to the delicatessen counter and purchase a few hundred grams of this and a few hundred grams of that. Sometimes a few hundred grams of the other. All relatively fat free, of course.
The nice lady behind the counter weighs my choices accurately, presses a magic button and prints out a price tag. She picks up the plastic bag with the goodies in it, twirls it, twiddles it, makes a magic gesture and sticks the price label to it. I take the bag from her and place it in my trolley. In the fullness of time I pay for it and take it home.
Round about lunchtime, fancying a sandwich, I take the bag of goodies out of the fridge. And every week I discover that the simple plastic bag with the turkey pastrami (or whatever) in it has turned into a Klein Bottle. I can see the turkey pastrami. I can feel the turkey pastrami through the convoluted folds of the bag. What I can't do is remove the turkey pastrami from the bag. No matter how I twist and turn the plastic, no matter which orifice I stick my hand into, the turkey pastrami remains just out of reach on the other side of the plastic. I follow every fold of the bag with my fingers and there is no doubt at all that the bag has become a three dimensional mobius strip. It only has one side and one edge and one surface. And the turkey pastrami isn't on any of them. It's hiding in plain view on the side that doesn't exist. And as I do every week, I have no alternative but to rip the bag to shreds. This collapses some sort of wave function, and it forces the bag to re-enter the same space-time continuum that I inhabit. Once more the bag has an inside and an outside; dimensions that previously were sorely lacking. The turkey pastrami is now available for my sandwich, but I'm too exhausted to eat it.
It's extremely frustrating!
Last week I was in Woolworths again. They had a vacancy in the delicatessen. There was an advert sellotaped to the glass:
Wanted -- someone to serve on the delicatessen counter. Must have an in depth knowledge of exotic meats and a passion for pork. Must be turned on by turkey, and must cherish chicken. Must be good with people. Must have an advanced degree in topology.