Also problematic is that the Wizarding world undervalues Galleons and overvalues Sickles. If he can pay the debt in 1.7 million Sickles, then he's fine- but if he has to pay them in Galleons, and he just modified the Galleon-Sickle exchange rate to 50-1, then he's worse off. (He might have made enough from the arbitrage to pay back Malfoy, but maybe not.)
Worst comes to worst, he asks Dumbledore to cure some rich muggles with cancer who are willing to pay.
[edit]Remember, the trick only needs to work once. Take out 40k galleons, convert it to muggle gold (probably necessary, but maybe not), convert it to 50 times as much silver by weight, convert it to Sickles, and now he has (if they're the same weight coins) 2M Sickles, minus conversion losses. Hand off 1.7M of them to Lucius (or get them changed at Gringotts), and the debt is cleared.
Now, Harry triples his money every time he does the trick- so he'll probably want to try it several times before losing a lot of his principal. But that's not a big issue.
Worst comes to worst, he asks Dumbledore to cure some rich muggles with cancer who are willing to pay.
I think that the can of worms of why wizards don't immediately go cure world hunger etc. is best left to be opened near the end of the fic, if at all.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 81, which should be published later today. The previous thread passed 400 comments as of the time of this writing, so it will pass 500 comments soon after the next chapter is posted, if not before. I suggest refraining from commenting here until chapter 81 is posted; comment in the 12th thread until you read chapter 81. After chapter 81 is posted, I suggest all discussion of previous guesses be kept here, with links to comments in the previous thread.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.) When posted, chapter 81 should appear here.
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: one, two, three, four, five, six, seven, eight,nine, ten, eleven, twelve.
As a reminder, it’s often useful to start your comment by indicating which chapter you are commenting on.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: