> Argh, again I'm temporarily unable to make new posts, so here goes my reply.

Please don't.

You don't understand hackernews. That's a feature of this website to slow down rambling discussions. In deep discussions take your time to answer. After a certain amount of time you can reply.

It's all in the Lisp code for this website.

> What's an incorrect program going to do about its own incorrectness? Rewrite itself?

There are a lot of options:

  * inform the next system to take over some functions
  * remove some features, while they are faulty, until patches are loaded in
  * use alternative implementations

Look at actual Flight Control Software. That's what it does and what it is designed.

Similar for other control systems, for example in power plants. They also need independent implementations controlling each other.

> Yeah, well, that's in itself precisely what's so terrible.

It's the reality. That's why mission critical systems don't believe that even verified software has no bugs.