Harry Potter and the Methods of Rationality (7 page)

But what Harry actually thought was,
Aw crap.

Harry turned his own head to scan the street. Nope, no one nearby. “He’s
not
dead, is he,” Harry sighed.

“Mr. Potter -”

“The Dark Lord is alive. Of
course
he’s alive. It was an
act
of utter
optimism
for me to have even
dreamed
otherwise. I
must
have taken leave of my
senses
, I can’t
imagine
what I was
thinking.
Just because
someone
said that his body was found burned to a
crisp
, I can’t imagine why I would have thought he was
dead.
Clearly
I have much left to learn about the art of proper
pessimism.
”

“Mr. Potter -”

“At least tell me there’s not really a prophecy…” Professor McGonagall was still giving him that bright, fixed smile. “Oh, you have
got
to be kidding me.”

“Mr. Potter, you shouldn’t go inventing things to worry about -”

“Are you
actually
going to tell me
that?
Imagine my reaction later, when I find out that there was something to worry about after all.”

Her fixed smile faltered.

Harry’s shoulders slumped. “I have a whole world of magic to analyse. I do
not
have time for this.”

Then both of them shut up, as a man in flowing orange robes appeared on the street and slowly passed them by; Professor McGonagall’s eyes tracked him, unobtrusively. Harry’s mouth was moving as he chewed hard on his lip, and someone watching closely would have noticed a tiny spot of blood appear.

When the orange-robed man had passed into the distance, Harry spoke again, in a low murmur. “Are you going to tell me the truth now, Professor McGonagall? And don’t bother trying to wave it off, I’m not stupid.”

“You’re
eleven years old
, Mr. Potter!” she said in a harsh whisper.

“And therefore subhuman. Sorry… for a moment there, I
forgot
.”

“These are dreadful and important matters! They are
secret,
Mr. Potter! It is a
catastrophe
that you, still a child, know even this much! You must not tell
anyone,
do you understand? Absolutely no one!”

As sometimes happened when Harry got
sufficiently
angry, his blood went cold, instead of hot, and a terrible dark clarity descended over his mind, mapping out possible tactics and assessing their consequences with iron realism.

Point out that you have a right to know: Failure. Eleven-year-old children do not have rights to know anything, in McGonagall’s eyes.

Say that you will not be friends any more: Failure. She does not value your friendship sufficiently.

Point out that you will be in danger if you do not know: Failure. Plans have already been made based on your ignorance. The
certain
inconvenience of rethinking will seem far more unpalatable than the mere
uncertain
prospect of your coming to harm.

Justice and reason will both fail. You must either find something you have that she wants, or find something you can do which she fears…

Ah.

“Well then, Professor,” Harry said in a low, icy tone, “it sounds like I have something you want. You can, if you like, tell me the truth, the
whole
truth, and in return I will keep your secrets. Or you can try to keep me ignorant so you can use me as a pawn, in which case I will owe you nothing.”

McGonagall stopped short in the street. Her eyes blazed and her voice descended into an outright hiss. “How dare you!”

“
How dare you!
” he whispered back at her.

“You would
blackmail
me?”

Harry’s lips twisted. “I am
offering
you a
favor.
I am
giving
you a chance to protect
your
precious secret. If you refuse I will have
every
natural motive to make inquiries elsewhere, not to spite you, but because I
have to know!
Get past your pointless anger at a
child
who you think ought to obey you, and you’ll realise that any sane adult would do the same!
Look at it from my perspective! How would you feel if it was YOU?
”

Harry watched McGonagall, observed her harsh breathing. It occurred to him that it was time to ease off the pressure, let her simmer for a while. “You don’t have to decide right away,” Harry said in a more normal tone. “I’ll understand if you want time to think about my
offer
… but I’ll warn you of one thing,” Harry said, his voice going colder. “Don’t try that Obliviation spell on me. Some time ago I worked out a signal, and I have already sent that signal to myself. If I find that signal and I don’t
remember
sending it…” Harry let his voice trail off significantly.

McGonagall’s face was working as her expressions shifted. “I… wasn’t thinking of Obliviating you, Mr. Potter… but why would you have
invented
such a signal if you didn’t know about -”

“I thought of it while reading a Muggle science-fiction book, and said to myself,
well, just in case…
And no, I won’t tell you the signal, I’m not dumb.”

“I hadn’t planned to ask,” McGonagall said. She seemed to fold in on herself, and suddenly looked very old, and very tired. “This has been an exhausting day, Mr. Potter. Can we get your trunk, and send you home? I will trust you not to speak upon this matter until I have had time to think. Keep in mind that there are only two other people in the whole world who know about this matter, and they are Headmaster Albus Dumbledore and Professor Severus Snape.”

So. New information; that was a peace offering. Harry nodded in acceptance, and turned his head to look forward, and started walking again, as his blood slowly began to warm over once more.

“So now I’ve got to find some way to kill an immortal Dark Wizard,” Harry said, and sighed in frustration. “I really wish you had told me that
before
I started shopping.”

The trunk shop was more richly appointed than any other shop Harry had visited; the curtains were lush and delicately patterned, the floor and walls of stained and polished wood, and the trunks occupied places of honor on polished ivory platforms. The salesman was dressed in robes of finery only a cut below those of Lucius Malfoy, and spoke with exquisite, oily politeness to both Harry and Professor McGonagall.

Harry had asked his questions, and had gravitated to a trunk of heavy-looking wood, not polished but warm and solid, carved with the pattern of a guardian dragon whose eyes shifted to look at anyone nearing it. A trunk charmed to be light, to shrink on command, to sprout small clawed tentacles from its bottom and squirm after its owner. A trunk with two drawers on each of four sides that each slid out to reveal compartments as deep as the whole trunk. A lid with four locks each of which would reveal a different space inside. And - this was the important part - a handle on the bottom which slid out a frame containing a staircase leading down into a small, lighted room that would hold, Harry estimated, around twelve bookcases.

If they made luggages like this, Harry didn’t know why anyone bothered owning a house.

One hundred and eight golden Galleons. That was the price of a good trunk, lightly used. At around fifty British pounds to the Galleon, that was enough to buy a second-hand car. It would be more expensive than everything else Harry had ever bought in his whole life all put together.

Ninety-seven Galleons. That was how much was left in the bag of gold Harry had been allowed to take out of Gringotts.

Professor McGonagall wore a look of chagrin upon her face. After a long day’s shopping she hadn’t needed to ask Harry how much gold was left in the bag, after the salesman quoted his price, which meant the Professor could do good mental arithmetic without pen and paper. Once again, Harry reminded himself that
scientifically illiterate
was not at all the same thing as
stupid.

“I’m sorry, young man,” said Professor McGonagall. “This is entirely my fault. I would offer to take you back to Gringotts, but the bank will be closed for all but emergency services now.”

Harry looked at her, wondering…

“Well,” sighed Professor McGonagall, as she swung on one heel, “we may as well go, I suppose.”

…she
hadn’t
lost it completely when a child had dared defy her. She hadn’t been happy, but she had
thought
instead of exploding in fury. It might have just been that there was an immortal Dark Lord to fight - that she had needed Harry’s goodwill. But most adults wouldn’t have been capable of thinking even that much; wouldn’t consider
future consequences
at all, if someone lower in status had refused to obey them…

“Professor?” Harry said.

The witch turned back and looked at him.

Harry took a deep breath. He needed to be a little angry for what he wanted to try now, there was no way he’d have the courage to do it otherwise.
She didn’t listen to me,
he thought to himself,
I would have taken more gold but she didn’t want to listen…
Focusing his entire world on McGonagall and the need to bend this conversation to his will, he spoke.

“Professor, you thought one hundred Galleons would be more than enough for a trunk. That’s why you didn’t bother warning me before it went down to ninety-seven. Which is just the sort of thing the research studies show - that’s what happens when people think they’re leaving themselves a
little
error margin. They’re not pessimistic enough. If it’d been up to me, I’d have taken
two hundred
Galleons just to be sure. There was plenty of money in that vault, and I could have put back any extra later. But I thought you wouldn’t let me do it. I thought you’d be angry at me just for asking. Was I wrong?”

“I suppose I must confess that you are right,” said Professor McGonagall. “But, young man -”

“That sort of thing is the reason why I have trouble trusting adults.” Somehow Harry kept his voice steady. “Because they get angry if you even
try
to reason with them. To them it’s defiance and insolence and a challenge to their higher tribal status. If you try to talk to them they get
angry.
So if I had anything
really
important
to do, I wouldn’t be able to trust you. Even if you listened with deep concern to whatever I said - because that’s also part of the
role
of someone playing a concerned adult - you’d never change your actions, you wouldn’t actually behave differently, because of anything I said.”

The salesman was watching them both with unabashed fascination.

“I can understand your point of view,” Professor McGonagall said eventually. “If I sometimes seem too strict, please remember that I have served as Head of Gryffindor House for what feels like several thousand years.”

Harry nodded and continued. “So - suppose I had a way to get more Galleons from my vault
without
us going back to Gringotts, but it involved me violating the role of an obedient child. Would I be able to trust you with that, even though you’d have to step outside your own role as Professor McGonagall to take advantage of it?”

“
What?
” said Professor McGonagall.

“To put it another way, if I could make today have happened differently, so that we
didn’t
take too little money with us, would that be all right even though it would involve a child being insolent to an adult in retrospect?”

“I… suppose…” the witch said, looking quite puzzled.

Harry took out the mokeskin pouch, and said, “Eleven Galleons originally from my family vault.”

And there was gold in Harry’s hand.

For a moment Professor McGonagall’s mouth gaped wide, then her jaw snapped shut and her eyes narrowed and the witch bit out, “
Where
did you get that -”

“From my family vault, like I said.”

“
How?
”

“Magic.”

“That’s hardly an answer!” snapped Professor McGonagall, and then stopped, blinking.

“No, it isn’t, is it? I
ought
to claim that it’s because I experimentally discovered the true secrets of how the pouch works and that it can actually retrieve objects from anywhere, not just its own inside, if you phrase the request correctly. But actually it’s from when I fell into that pile of gold before and I shoved some Galleons into my pocket. Anyone who understands pessimism knows that money is something you might need quickly and without much warning. So now are you angry at me for defying your authority? Or glad that we succeeded in our important mission?”

The salesman’s eyes were wide like saucers.

And the tall witch stood there, silent.

“Discipline at Hogwarts
must
be enforced,” she said after almost a full minute. “For the sake of
all
the students. And that
must
include courtesy and obedience from you to
all
professors.”

“I understand, Professor McGonagall.”

“Good. Now let us buy that trunk and go home.”

Harry felt like throwing up, or cheering, or fainting, or
something
. That was the first time his careful reasoning had ever worked on
anyone
. Maybe because it was also the first time he had something really serious that an adult needed from him, but still -

Minerva McGonagall, +1 point.

Harry bowed, and gave the bag of gold and the extra eleven Galleons into McGonagall’s hands. “Thank you very much, Professor. Can you finish up the purchase for me? I’ve got to visit the lavatory.”

The salesman, unctuous once more, pointed toward a door set into the wall with a gold-handled knob. As Harry started to walk away, he heard the salesman ask in his oily voice, “May I inquire as to who that was, Madam McGonagall? I take it he is Slytherin - third-year, perhaps? - and from a prominent family, but I did not recognise -”

The slam of the lavatory door cut off his words, and after Harry had identified the lock and pressed it into place, he grabbed the magical self-cleaning towel and, with shaky hands, wiped moisture off his forehead. Harry’s entire body was sheathed in sweat which had soaked clear through his Muggle clothing, though at least it didn’t show through the robes.