# Harry Potter and the Methods of Rationality

Are you a Harry Potter fan? And a skeptic? I command you to go bookmark this fanfiction and read it immediately (well, immediately after blogathon is over). It’s called Harry Potter and the Methods of Rationality. It’s set in an alternate universe where Harry’s adoptive father is an Oxford professor, and thus Harry is extremely well trained as a skeptical thinker.

I know what you’re thinking. “Come on, fanfiction, Jen? Didn’t you graduate middle school years ago?” But trust me – if you’re one of those people who liked to over analyze the Harry Potter universe, you have to read this fic. I’ve spent many geeky hours pondering the possible genetic inheritance pattern of magical ability. Or how horrible the English and critical thinking skills of wizards and witches must be if they stopped their traditional education at age 11. If you haven’t thought these things, you will now. For example, here’s a snippet of Harry pondering about the economy of the Wizarding World:

So not only is the wizarding economy almost completely decoupled from the Muggle economy, no one here has ever heard of arbitrage. The larger Muggle economy had a fluctuating trading range of gold to silver, so every time the Muggle gold-to-silver ratio got more than 5% away from the weight of seventeen Sickles to one Galleon, either gold or silver should have drained from the wizarding economy until it became impossible to maintain the exchange rate. Bring in a ton of silver, change to Sickles (and pay 5%), change the Sickles for Galleons, take the gold to the Muggle world, exchange it for more silver than you started with, and repeat.

Wasn’t the Muggle gold to silver ratio somewhere around fifty to one? Harry didn’t think it was seventeen, anyway. And it looked like the silver coins were actually smaller than the gold coins.

Then again, Harry was standing in a bank that literally stored your money in vaults full of gold coins guarded by dragons, where you had to go in and take out coins out of your vault whenever you wanted to spend money. The finer points of arbitraging away market inefficiencies might well be lost on them. He’d been tempted to make some sort of snide remark about the crudity of their financial system…

But the sad thing is, their way is probably better.

On the other hand, one competent hedge fundie could probably own the whole wizarding world within a week. Harry filed away this notion in case he ever ran out of money, or had a week free.

Not only is it hilarious, but it’s also full of such good information that it works as a primer to skeptical thinking. Read until Chapter 5 to give it a chance, and if you don’t like it by 10, give up. It’s a quick read, but dangerously addictive.

Thanks to Jesse Galef for showing me this right before Blogathon, thus ruining many hours of productivity for me.

This is post3 of 49 of Blogathon. Pledge a donation to the Secular Student Alliance here.

1. Jesse Galef says

I do it because I care. Blogathon is just too EASY if you’re not distracted by anything. Seriously, so glad you like it! (It shows good taste.) I look forward to talking with you about it later.

2. says

Ben told me about this and I had nearly forgotten about it – thanks for posting this! I think it’ll be right up my ally as a skeptic, a Harry Potter fan who has actually criticized the juvenile methods of a community too dependent on magic, and even likes to get involved in fandom still. It’s absurdly hard to find decent fanfiction, but when I do it’s always inspiring!

3. says

Oh my god!! I’m on my first day off work in a week or two (luckily it was on blogathon), and this is going to completely consume the part of it that isn’t spent reading your posts… I absolutely love this excerpt, and if the rest is just as good, I may just be put onto fanfics. Thanks! Definitely not sacrificing interesting content in order to get 49 posts done =P

4. erika ebullient says

I’ve been reading this fanfic for weeks! It is incredibly fun to read, and if you like the rationality lessons in the story, you should check out lesswrong.com (a blog whose most frequent contributor is the same author), and wiki.lesswrong.com (a series of posts designed to introduce people to rationality in general and bayesian reasoning in specific).THANK YOU for sending other people to this. I’m so thrilled the author is gaining recognition.

5. the_Siliconopolitan says

Heh. Heh. Heh.Unfortunately it’s hard to picture Harry ever being that perceptive. But not my fandom, so what do I know?(Good guess, though. ::wiggles x-dollar bill in front of you::)

6. Just read the first chapter, and I must say… this is like harry potter for adults.Or thinkers…I hope he does the whole series. Of course it would end really quick when harry whips out science on Voldermort, or a gun really…

7. StephenS says

Thank you, Jen, for providing something to read while I’m waiting for new blogathon posts or their comments.

8. Alex says

I’m usually not into fanfics, but this is definitely interesting. I’ll have to bookmark to read some more later.

9. Aw hell yes. I’ve been reading this since about chapter six or seven, and I’ve gotten to the point where when a new chapter is posted I drop everything to read it. Fanfiction is sort of my vice to begin with, but this is one piece that I want to run out on the street and show to everyone I meet.

10. guest says

I’ve been reading lesswrong for a while now (since before it was around, actually), and I love it. If you like that kind of fiction, you might want to check out this page as well, which has similar short fiction stories that mix rationality with sci-fi or fantasy.

11. mcbender says

This is absolutely brilliant, although I’m somewhat nervous about saying that about a fanfiction (not a genre I normally read). Nevertheless, I read the entire thing today in one sitting; then I started over from the beginning and read it again – so much for productivity, as it ate pretty much my entire day.That said… while it’s entertaining and does a great job of incorporating lots of interesting science, I find it difficult to maintain the suspension of disbelief while reading it because all of the children – not just Genius Harry – are far too perceptive and clever to be believable (especially in contrast to the adults). Maybe that’s the point, but at times it’s distracting.

12. says

I know it’s been nearly a year since this post went up, but I’m now putting this into audio book form for those who don’t have the time to read. Another chapter is published every Wednesday.http://itunes.apple.com/us/pod

13. msapa says