Showing posts with label Kurt Gödel. Show all posts
Showing posts with label Kurt Gödel. Show all posts

Tuesday, September 29, 2009

Incompleteness

I'm with Gödel, said Pliny the Elder. The world is not everything that is the case. I haven't received my book yet, although I've paid for it, and that's a fact.

I don't think Gödel's theorem was concerned with things that hadn't arrived yet, I said doubtfully. I think it was only to do with arithmetical truths. That some things arithmetical are true but unprovable, in any consistent theory.

Well, said Pliny, It's true but unprovable that I haven't got my book. How do you prove that you haven't got something?

You're right you can't, I agreed. But it's not the Incompleteness Theory.

Yes it is, said Pliny. My transaction in buying the book is incomplete without the book. And you can't tell me that a monetary transaction is not arithmetical.

I think you have won the argument, I said. Gödel's theorem is more useful than I thought.

Monday, September 28, 2009

All That is the Case

I'm sitting out the back at a wooden table reading a book. Trying not to lean too hard on my blue and green striped elbows. There's grit on the table.

The wind blows the shadow strands of my hair over the pages. I look up. I see something moving on the low wall near the rosemary and pencil pine, above the black pot. It looks like a tiny white and ginger mouse, or a chicken. I look harder. It's a feather, ginger at each end and white in the middle. The feather is attached by invisible threads to the brick wall. The wind is making it twist and toss and rock back and forth and seem to be pecking the air.

Now I know that it's not alive, it loses my sympathy. And immediately regains it. What makes it not alive anyway? It's moving as though it's alive. What's the difference? It's trapped. But it isn't going to die there. It loses my sympathy again.

I go back to my book, which is about Kurt Gödel the mathematician. I'm reading the words of Wittgenstein: The world is everything which is the case. Kurt Gödel is just about to present to his philosophical and mathematical friends in the Viennese coffee shop, proof that the world is not everything that is the case. I like this.

It's warm. I go inside. There's some orange stuck in my teeth, from lunch. I'm thinking about the feather. I'm thinking: after I've got rid of the orange I'll go and look at that feather close up. I get some dental floss. I walk outside still flossing. I hope no one can see me. I bend down and look at the feather.

It is in fact two feathers, each with a ginger tip, and joined in the middle by white fluffy down. They are caught on a filament of dried grass sticking up between the bricks. This is why they looked like a chicken.

I like this too.