ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
From previous post:
Spoiler Warning: this thread contains unrot13'd spoilers for Harry Potter and the Methods of Rationality up to the current chapter and for the original Harry Potter series. Please continue to use rot13 for spoilers to other works of fiction, or if you have insider knowledge of future chapters of Harry Potter and the Methods of Rationality.
A suggestion: mention at the top of your comment which chapter you're commenting on, or what chapter you're up to, so that people can understand the context of your comment even after more chapters have been posted. This can also help people avoid reading spoilers for a new chapter before they realize that there is a new chapter.
"Why," I said to myself, "would you have to die to make a ghost? It seems completely arbitrary." But then I thought that perhaps death releases a huge amount of magic that can't normally be drawn upon safely.
But then I had this wicked awesome idea.
What if a Horcrux is the same effect, harnessed deliberately? That's why it requires human sacrifice -- the violent death of a wizard. A controlled ghost-making, operated by a wizard who remains conscious and alive through the whole process, can bind the mind into an object, arrange for contingent regrowth of the caster from the record... Yes. Horcruxes are ghosts created under controlled conditions.
Which in turn suggests that you might be able to make a dying person into a superghost (or maybe even an immortal living person). Kill them to make a horcrux, but make the sacrifice immortal instead of the caster.
That’s a cool idea! Also, it nicely has an analogue property to cryonics: you need to do something squicky (kill the guy) to save his life, in a fashion. Since the results would be closer in time and less speculative, it should overcome part of the revulsion of cryonics but allow the rest of it be overcome consciously.