Harry Potter and the Methods of Rationality Quotes

“For an instant Harry imagined... Just for an instant, before his imagination blew a fuse and called an emergency shut down and told him never to imagine that again.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“You can never have enough books. But you certainly tried. It was a really, really, really good try.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“If it was a friend, perhaps, you would have felt far more injured by what he said."
"If he were a friend, all the more reason to forgive him.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“(...) Where are you trying to go?”
Harry hesitated. “I’m not really sure,” he said.
“Then perhaps you are already there.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“What happened to me personally is only anecdotal evidence," Harry explained. "It doesn't carry the same weight as a replicated, peer-reviewed journal article about a controlled study with random assignment, many subjects, large effect sizes and strong statistical significance.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Nonviolent ideals were cheap to hold if you were a scientist, living inside the Protego bubble cast by the police officers and soldiers whose actions you had the luxury to question.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“During World War II, there had been a project to sabotage the Nazi nuclear weapons program. Years earlier, Leo Szilard, the first person to realize the possibility of a fission chain reaction, had convinced Fermi not to publish the discovery that purified graphite was a cheap and effective neutron moderator. Fermi had wanted to publish, for the sake of the great international project of science, which was above nationalism. But Szilard had persuaded Rabi, and Fermi had abided by the majority vote of their tiny three-person conspiracy. And so, years later, the only neutron moderator the Nazis had known about was deuterium.

The only deuterium source under Nazi control had been a captured facility in occupied Norway, which had been knocked out by bombs and sabotage, causing a total of twenty-four civilian deaths.

The Nazis had tried to ship the deuterium already refined to Germany, aboard a civilian Norwegian ferry, the SS Hydro.

Knut Haukelid and his assistants had been discovered by the night watchman of the civilian ferry while they were sneaking on board to sabotage it. Haukelid had told the watchman that they were escaping the Gestapo, and the watchman had let them go. Haukelid had considered warning the night watchman, but that would have endangered the mission, so Haukelid had only shaken his hand. And the civilian ship had sunk in the deepest part of the lake, with eight dead Germans, seven dead crew, and three dead civilian bystanders. Some of the Norwegian rescuers of the ship had thought the German soldiers present should be left to drown, but this view had not prevailed, and the German survivors had been rescued. And that had been the end of the Nazi nuclear weapons program.

Which was to say that Knut Haukelid had killed innocent people. One of whom, the night watchman of the ship, had been a good person. Someone who'd gone out of his way to help Haukelid, at risk to himself; from the kindness of his heart, for the highest moral reasons; and been sent to drown in turn. Afterward, in the cold light of history, it had looked like the Nazis had never been close to getting nuclear weapons after all.

And Harry had never read anything suggesting that Haukelid had acted wrongly.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“But what happens after you break - that, too, is part of being a hero.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“As you would be kind to others, be kinder to yourself as well.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“It wasn't that Harry had gone down the wrong path, it wasn't that the road to sanity lay somewhere outside of science. But reading science papers hadn't been enough. All the cognitive psychology papers about known bugs in the human brain and so on had helped, but they hadn't been sufficient. He'd failed to reach what Harry was starting to realise was a shockingly high standard of being so incredibly, unbelievably rational that you actually started to get things right,as opposed to having a handy language in which to describe afterwards everything you'd just done wrong. Harry could look back now and apply ideas like 'motivated cognition' to see where he'd gone astray over the last year. That counted for something, when it came to being saner in the future. That was better than having no idea what he'd done wrong. But that wasn't yet being the person who could pass through Time's narrow keyhole, the adult form whose possibility Dumbledore had been instructed by seers to create.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“It was a rare brain that could feel strongly about anything, if it wasn't close in space, close in time, near at hand, within easy reach...”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“When you walked through a park, the immersive world that surrounded you was something that existed inside your own brain as a pattern of neurons firing. The sensation of a bright blue sky wasn't something high above you, it was something in your visual cortex, and your visual cortex was in the back of your brain. All the sensations of that bright world were really happening in that quiet cave of bone you called your skull, the place where you lived and never, ever left. If you really wanted to say hello to someone, to the actual person, you wouldn't shake their hand, you'd knock gently on their skull and say "How are you doing in there?" That was what people were, that was where they really lived. And the picture of the park that you thought you were walking through was something that was visualized inside your brain as it processed the signals sent down from your eyes and retina.

It wasn't a lie like the Buddhists thought, there wasn't something terribly mystical and unexpected behind the veil of Maya, what lay beyond the illusion of the park was just the actual park, but it was all still illusion.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“But then human beings only understood each other in the first place by pretending. You didn't make predictions about people by modeling the hundred trillion synapses in their brain as separate objects. Ask the best social manipulator on Earth to build you an Artificial Intelligence from scratch, and they'd just give you a dumb look. You predicted people by telling your brain to act like theirs. You put yourself in their place. If you wanted to know what an angry person would do, you activated your own brain's anger circuitry, and whatever that circuitry output, that was your prediction. What did the neural circuitry for anger actually look like inside? Who knew? The best social manipulator on Earth might not know what neurons were, and neither might the best Legilimens.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“When there are lots of possibilities, most of the work goes into just locating the true answer - starting to pay attention to it. You don't need proof, or the sort of official evidence that scientists or courts demand, but you need some sort of hint, and that hint has to discriminate that particular possibility from the millions of others. Otherwise you can't just pluck the right answer out of thin air. You can't even pluck a possibility worth thinking about out of thin air.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“The point being that when there are lots of possible answers, most of the evidence you need goes into just locating the true hypothesis out of millions of possibilities - bringing it to your attention in the first place. The amount of evidence you need to judge between two or three plausible candidates is much smaller by comparison. So if you just jump ahead without evidence and promote one particular possibility to the focus of your attention, you're skipping over most of the work.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“I will reluctantly teach you enough trivia for a passing mark on the Ministry-mandated portions of your first-year finals. Since your exact mark on these sections will make no difference to your future life, anyone who wants more than a passing mark is welcome to waste their own time studying our pathetic excuse for a textbook. The title of this subject is not Defence Against Minor Pests. You are here to learn how to defend yourselves against the Dark Arts. Which means, let us be very clear on this, defending yourselves against Dark Wizards. People with wands who want to hurt you and who will likely succeed in doing so unless you hurt them first! There is no defence without offence! There is no defence without fighting! This reality is deemed too harsh for eleven-year-olds by the fat, overpaid, Auror-guarded politicians who mandated your curriculum. To the abyss with those fools! You are here for the subject that has been taught at Hogwarts for eight hundred years! Welcome to your first year of Battle Magic!”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Up until this point Harry had lived by the admonition of E. T. Jaynes that if you were ignorant about a phenomenon, that was a fact about your own state of mind, not a fact about the phenomenon itself; that your uncertainty was a fact about you, not a fact about whatever you were uncertain about; that ignorance existed in the mind, not in reality; that a blank map did not correspond to a blank territory. There were mysterious questions, but a mysterious answer was a contradiction in terms. A phenomenon could be mysterious to some particular person, but there could be no phenomena mysterious of themselves. To worship a sacred mystery was just to worship your own ignorance.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Trying to navigate the halls of Hogwarts was like... probably not quite as bad as wandering around inside an Escher painting, that was the sort of thing you said for rhetorical effect rather than for its being true.

A short time later, Harry was thinking that in fact an Escher painting would have both pluses and minuses compared to Hogwarts. Minuses: No consistent gravitational orientation. Pluses: At least the stairs wouldn't move around WHILE YOU WERE STILL ON THEM.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Charming, happy, generous with his favors to his friends, Draco wasn't a psychopath. That was the sad and awful part, knowing human psychology well enough to know that Draco wasn't a monster. There had been ten thousand societies over the history of the world where this conversation could have happened. No, the world would have been a very different place indeed, if it took an evil mutant to say what Draco had said. It was very simple, very human, it was the default if nothing else intervened. To Draco, his enemies weren't people.

And in the slowed time of this slowed country, here and now as in the darkness-before-dawn prior to the Age of Reason, the son of a sufficiently powerful noble would simply take for granted that he was above the law, at least when it came to some peasant girl. There were places in Muggle-land where it was still the same way, countries where that sort of nobility still existed and still thought like that, or even grimmer lands where it wasn't just the nobility. It was like that in every place and time that didn't descend directly from the Enlightenment. A line of descent, it seemed, which didn't quite include magical Britain, for all that there had been cross-cultural contamination of things like ring-pull drinks cans.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“You're mine now, Harry thought at the walls of Diagon Alley, and all the shops and items, and all the shopkeepers and customers; and all the lands and people of wizarding Britain, and all the wider wizarding world; and the entire greater universe of which Muggle scientists understood so much less than they believed. I, Harry James Potter-Evans-Verres, do now claim this territory in the name of Science.

Lightning and thunder completely failed to flash and boom in the cloudless skies.

"What are you smiling about?" inquired Professor McGonagall, warily and wearily.

"I'm wondering if there's a spell to make lightning flash in the background whenever I make an ominous resolution," explained Harry. He was carefully memorising the exact words of his ominous resolution so that future history books would get it right.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Then again, it'd taken more than two hundred years after the invention of the scientific method before any Muggle scientists had thought to systematically investigate which sentences a human four-year-old could or couldn't understand. The developmental psychology of linguistics could've been discovered in the eighteenth century, in principle, but no one had even thought to look until the twentieth. So you couldn't really blame the much smaller wizarding world for not investigating the Retrieval Charm.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“The golden coins might have been his, but they were still stolen - self-stolen? Auto-thieved?”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Twenty years later, that was what he would desperately wish had happened twenty years ago, and twenty years before twenty years later happened to be right now. Altering the distant past was easy, you just had to think of it at the right time.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Never give anyone wise advice unless you know exactly what you're both talking about.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“That which can be destroyed by the truth should be”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“I'm not stupid, Mr. Potter. What's the real reason you didn't tell me, and what were you actually doing with Mr. Malfoy?"

"Ah. Well..." Harry broke eye contact with her, and looked down at the library table.

"Draco Malfoy told the Aurors under Veritaserum that he wanted to know if he could beat me, so he challenged me to a duel to test it empirically. Those were his exact words according to the transcript."

"Right," Harry said, still not meeting her eyes. "Hermione Granger. Of course she'll remember the exact wording. It doesn't matter if she's chained to her chair, on trial for murder in front of the entire Wizengamot -"

"What were you really doing with Draco Malfoy?"

Harry winced, and said, "Probably not quite what you're thinking, but..."

The horror scaled and scaled within her, and finally broke loose.

"You were doing SCIENCE with him? "

"Well -"

"You were doing SCIENCE with him? You were supposed to be doing science with ME! ”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“All right," Harry said coldly. "I'll answer your original question, then. You asked why Dark Wizards are afraid of death. Pretend, Headmaster, that you really believed in souls. Pretend that anyone could verify the existence of souls at any time, pretend that nobody cried at funerals because they knew their loved ones were still alive. Now can you imagine destroying a soul? Ripping it to shreds so that nothing remains to go on its next great adventure? Can you imagine what a terrible thing that would be, the worst crime that had ever been committed in the history of the universe, which you would do anything to prevent from happening even once? Because that's what Death really is - the annihilation of a soul!”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“Do not think that heroes cannot be broken! We are only more difficult to break, Hermione." The old wizard's eyes had grown sterner than she had ever seen. "When you have been exhausted for many hours, when pain and death is not a passing fear but a certainty, then it is harder to be a hero.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“But Father had once told her that the trouble with passing up opportunities was that it was habit-forming. If you told yourself you were waiting for a better opportunity next time, why, next time you'd probably tell yourself the same thing. Father had said that most people spent their whole lives waiting for an opportunity that was good enough, and then they died. Father had said that while seizing opportunities would mean that all sorts of things went wrong, it wasn't nearly as bad as being a hopeless lump. Father had said that after she got into the habit of seizing opportunities, then it was time to start being picky about them.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality

“This was made for you, I think. For the person you're going to become."

A weapon to fight Death, in its form as the shadow of despair that falls on human minds and drains away their hope for the future.”
― Eliezer Yudkowsky, Harry Potter and the Methods of Rationality