Harry James Potter-Evans-Verres receives his letter of invitation from Hogwarts. He and his loving adoptive father are, understandably, sort of baffled at the notion that magic exists at all. They ask that a Hogwarts professor give them a demonstration, in person, in order to convince them. And so, Minerva McGonagall shows up at the Evans-Verres house, in Oxford, and turns into a cat.

And Harry screams in horror, instantaneously realising what that means for the principle of conservation of mass-energy.

This scene is perhaps one of the best introductions possible to what “Harry Potter and the Methods of Rationality” by LessWrong (HPMOR from now on) and its officially approved sequel, “Significant Digits” by Alexander D., are. As far as HP fanfictions go, HPMOR might just be the most famous. The two together have such a huge word count they probably surpass the entire original seven book saga, and cover a world of even larger scope (as they can afford to skip on some of the world building by relying on your knowledge of the canon lore). Half fantasy, half sci-fi, with equal parts affectionate parody and philosophical pamphlet, and occasionally better written and plotted than Rowling’s own work, HPMOR has been both widely internet-famous and somewhat controversial. Fresh of a re-read, I’ll try reviewing it, why it’s interesting and why it might or might not be for you. I’ll try to keep this spoiler-free which means I’ll also avoid discussing some of the most specific issues that have been raised, but hopefully, I’ll still make my point come across.

First, a disclaimer. A lot of people are put off from reading HPMOR by the reputation of its author, so I’ll lay that immediately in the open for those who don’t know and discuss my ideas on it. Eliezer Yudkowsky, aka LessWrong, is an Artificial Intelligence researcher, founder of the Machine Learning Research Institute. He also is a staunch believer in the Technological Singularity. In other words, he thinks that the meteoric rise in computational power and sophistication of AI will inevitably lead to the development of an exponentially self-improving intelligent machine that will soon rise to the status of physical god. Given the inevitability of such a prospect, he believes the only sensible thing to do is try and be the first to develop such an AI, so that at least one can exert control over its programming and have it be benign instead of oblivious to human destinies or, worse, malicious. With enough intelligence, he thinks, all problems of mankind will be solved, and even immortality might not be a pipe dream any more. So basically if you want to live forever and not be dominated by Skynet, donate to his foundation.

Needless to say, this vision sounds rather nuts for a number of reasons. Personally I am highly sceptical that anything like an infinite rise in informational processing power at exponential rate could ever happen in a world with so many physical limits as ours. That said, I think Yudkowsky genuinely believes all of this, and it’s not just a scam for the sake of money. Which doesn’t make it less extreme, but at least means he’s in good faith. Now, normally, I’m an advocate for separation of art and artist, but in this case there’s really no way to do that. HPMOR is undoubtedly drenched in these ideas, while expressed in a less strong form and more or less believably interwoven in the story. There’s discussion of transhumanism and singularity and Yudkowsky’s own research on Bayesian decision theory all over the place in it. So, ultimately, I guess the real question is: does the fact that HPMOR is fundamentally a mouthpiece for its author’s own views affect its quality for me?

The answer, for me, is: not really. I can understand what Yudkowsky’s doing through the fanfiction, and it does not always work or convince me, but it does not affect my enjoyment much, because there’s also cleverly written characters who act as foils for Harry’s (namely, Yudkowsky’s) own ideas, and they’re not mere straw men. More so, the fanfiction was written a few years ago and seems to exhibit a more nuanced and less extreme view; and more importantly, in-universe, these views make a lot more sense. The entire premise of it is, in fact, that Harry Potter finding out magic convinces him that the laws of thermodynamics aren’t as binding as he thought them to be. In that kind of context, well, I might just be convinced that infinite exponential growth is indeed a possibility. But I haven’t received a letter from Hogwarts yet (hurry up, guys, I’m 32 already!), so given the information available to me, I don’t.

On to the meat then. What is HPMOR about? Well, it’s basically a complete rewriting of the whole story of Harry Potter, as it would unfold if instead of being raised by a cartoonishly abusive uneducated British family he’d grown up in a loving and scientifically very well-read household. Young Harry James Potter-Evans-Verres, as in this version he’s understandably proud enough of his adoptive parents to want to bear both their surnames, is an incredibly smart and incredibly nerdy kid who is sudden confronted with the reality of magic, and what that means for everything he’s ever believed. This works in a number of ways. On the most obvious layer, it provides a way for the writer to affectionately lampoon the many absurdities and contradictions of Rowling’s world, and that is one of the greatest sources of humour of the story. It also becomes a sort of self-deprecating nerd joke – Harry Potter in this version is often the worst, especially when it comes to his non-existent social graces. It provides an excellent set up to a number of amazingly geeky punch-lines (my favourite would be what happens when Harry tries to use a Time Turner to factorise a number into primes. Good stuff). But most importantly, it lays the foundations of a legitimately good story. To be clear, this is not a simple ‘what if’ – a number of other things, besides Harry’s own story, are different. So as the whole plot unfolds (though this time it all happens throughout only the first year), genuine plot twists await the reader, especially if one tries to rely too much on the knowledge of the books. The original lore is occasionally followed and occasionally subverted, and the end result is unpredictable enough to be gripping.

On to the characters. While Harry is still the obvious protagonist, Hermione enjoys a significant improvement in her role – to the point of becoming a co-protagonist, and in my opinion, of receiving much more justice than she ever did in the original. Ron gets demoted to an extra (admittedly, this Harry could not find much of interest in his company) while Draco ascends to third member of the trio, him and Harry playing a sophisticate psychological game with each other as they try to change the other’s worldview. House Slytherin, in general, is given much more attention and a much less harsh treatment than in the original books (it is a frequent flaw of Rowling’s, frankly, to just define characters as ‘evil’ for convenience and leave them at that, and that is something that this story addresses fully, in one of its most serious criticisms of the canon). And while Minerva McGonagall, Severus Snape and Albus Dumbledore stay all relevant, amongst the teachers, it’s the originally very bland Quirinus Quirrell who grabs all the attention by becoming a mentor of sorts to Harry while possibly having a shady secret he’s trying to hide…

Quirrel’s influence and dialogue in fact are a huge part of what makes the story fascinating. He contributes to some of the best bits of the fanfiction, by providing subtle and insidious amoral arguments that clash against Harry’s wholesale humanist worldview; and he sets up a system of mock battles that replaces Quidditch as a sports-like activity subplot, and is heavily inspired by “Ender’s Game”. The battles are not all vital to the plot, but they’re fun, engaging, and peppered with clever strategies and twists. If you ever enjoyed that book, this part is something you’ll be happy with as well.

So what about the negatives? Well, the fanfiction is long. Perhaps a bit too much so. It can get meandering, and especially when Harry starts being obnoxious and explain in great detail his ideas on the scientific method it occasionally gets repetitive. This all comes with the territory of the author not being able to keep himself from speaking through his character’s mouth, basically, which makes for some of the most awkward bits of dialogue. Most importantly, you could find yourself in philosophical disagreement with the views expressed, and that may affect your enjoyment. Personally I’m pretty okay with it, and even when I disagree it’s not by such a huge margin as for it to bother me, but it’s definitely a possibility.

This is an interesting point where to start talking about Significant Digits, in fact. I won’t go into many details as the story is set several years after the original, and any information about characters and events would imply spoilers about HPMOR, but if there’s one thing to be said, it’s that the different author’s perspective is obvious, and in fact, taken in pair, these two works might come off better than individually. Digits is, unfortunately, less uproariously funny than the most lighthearted moments of HPMOR, but it is also much more nuanced. The first impression I got is that if HPMOR was obviously written by a scientist, Digits felt like it was written by a lover of the humanities. There’s a lot of literary quotes, there’s extracts from fictional texts in believable old English, and there’s a general sense of more maturity and less blind faith in the march of progress than it was seen in HPMOR. Social and political struggles take front and centre, and the core issue is the conflict between those who want to advance technology and those who fear the danger that power could pose to the world, which is ever more relevant. Without saying much more, I think in hindsight Digits helps re-frame HPMOR as a story about Harry being young and foolish, and as such it changes the context of those rants I mentioned earlier. Whether this would be enough for you to save the whole affair is a subjective matter; but personally, I can only suggest that if any of this sounds remotely interesting to you, you just check them out personally. They’re out there and they’re free, after all. You could definitely read worse.

Also, if you will afford me a little spoiler – while in the canon one of the Weasley twins dies and the other loses an ear, here they team up with Neville Longbottom to form a badass team of hit wizards that ousts African warlords. And that must be worth something.