O-ring theory is a theory of economic development proposed in 1993 by Michael Kremer. It has been expanded on since then, most famously by Garett Jones, who did work to show how this model could play out on the international stage.

The titular o-ring refers to the faulty o-ring that caused the Challenger shuttle to explode in 1986. The space shuttle was perhaps one of the most technologically advanced machines that the human race had ever produced, with billions of dollars spent its development and construction; but regardless of the expertise put into its construction, it was only as strong as its weakest part, and that single point of failure caused the rest to fail catastrophically.

Kremer proposed that this cautionary tale works as an analogy to explain the way that economies succeed, fail, and self-organize. It states that an economic network is only as strong as its weakest point, and from this, many things follow. As an example of how this plays out…

I learned recently that the later Anglo-Saxon period of England had the local lords engaging in an eternal competition for greater wealth. The threat of downward social mobility among the Thanes drove them to seek greater surplus that they could exchange for currency, thus to maintain wealth and power.

To achieve this they began to demand more productivity from the land and more rent from the farmers. Where…

It's the same dream, over and over.

It's finally time to buy a house together. We've been living with your parents for a few years now, saving money. It's a good thing we get along so well with them. The deposit is saved and we've started to look at -

But I already own a house. I bought it with him, years ago. I just don't remember where -

We're looking in the southern suburbs, somewhere sensible. There's a place -

The address, I can't…