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Riddles in the Dark

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It was a quiet night in the Doctor’s bedroom – or rather, it would have been a quiet night had Jamie not been snoring quite so loudly.

Also, there was the voice yelling inside the Doctor’s head, and for once it wasn’t the usual one telling him he was acting the idiot. No, this was an entirely different and even more annoying voice.


“There’s no need to shout,” the Doctor replied mentally. “I can hear you perfectly fine, whoever you are.”

“I am the Great Intelligence –”

“Oh dear, you again? Shouldn’t you be floating about in space?”

“In your haste to depart London, you left your TARDIS’ shields deactivated. It was a simple matter to breach your security protocols and enter your ship.”

“Ah, how silly of me. I don’t suppose you’d consider leaving? No? Well, there’s nothing for it; we’ll simply have to entertain ourselves until Jamie wakes up. Do you know any campfire songs? Or we could play a round of two-handed cribbage – oh, that’s right, you haven’t any hands.”

“Your primitive forms of entertainment are irrelevant to me, Doctor. What I want is your knowledge, and that I shall have.”

The Doctor sighed. Villains, all of a piece; all wanting ultimate power, just in different forms. The least one of them could do would be to come up with something novel, although he had to admit that the otherwise-terrifying robotic yeti had had a certain fuzzy and no-doubt unintended charm.

“I’m flattered that you like my brain so much. I rather like it, too,” the Doctor said. “I propose a contest. A battle of wits, if you will: three questions, and each of us must guess the other’s answer. Surely if you’re indeed a ‘great intelligence,’ such a challenge ought to be no real challenge at all.”

“I already have your TARDIS, Doctor. Why should I agree to your terms?”

“Because you’ll never take this brain without a fight, and you know a mind such as mine is capable of destroying itself if it must. Win this contest, and I will willingly submit to you. Lose, and you leave my ship, never to return or seek me out again.”

The Doctor’s mind fell quiet while the Great Intelligence contemplated the offer. This provided the Doctor with several high-quality seconds of free time: 1.76 seconds to work out his three questions; 0.92 to gaze lovingly at the young man dozing beside him; and 0.32 to consider breakfast options for later. Soft-boiled eggs and toast soldiers, perhaps, washed down with a nice, strong cup of tea. Assam; yes, that would do.

“I agree to your terms,” the Great Intelligence finally said, “provided the final question of the three is mine.”

“That gives you an advantage – but I’ll allow it if I should have one final question in the event of a draw.”

“There will be no draw, Doctor, but as you wish.”

The Doctor settled back in his bed and tented his fingers over his chest. “Then let’s begin. What walks on ten legs in the morning, five legs in the afternoon, and nine legs in the evening?”

The Great Intelligence chuckled, a noise not entirely unlike the rheumy cough of a dying sheep.

“Too easy, Doctor. It’s a Venusian: a child on all tens, an adult on its five legs, and an elder with a Zimmer frame. I claim the advantage, one-nil.”

“A simple test,” the Doctor said. “I was merely assessing your abilities.”

“And now, I shall assess yours. Prove that for any positive integer values of a, b, and c, no number greater than 2 can satisfy the equation an + bn = cn.”

“A children’s nursery game? Really?”

“Your answer, Doctor.”

The Doctor sighed. “Very well. First, we need to discuss elliptical curves and rational numbers ...”

Some time later, during which Jamie had flopped onto his back and snored all the way through a spirited description of Fourier expansions, the Doctor finally completed his proof.

“I believe that brings us even now, does it not? So, your second question,” he said. “How much dirt is there in a hole 2 meters by 1.75 meters by 3.25 meters?”

“A trick question! There is no dirt in a hole!”

“Blast,” said the Doctor, “I could have sworn that one would get you.”

“You underestimate me, Doctor, and because of that, you shall lose.”

“Talk, as the saying goes, is cheap. Are you going to ask a question, or are you simply going to boast all night? Because I must say, that’s rather tiresome.”

The Great Intelligence might have been invisible, but the snarl in its voice was unmistakable. “In that case, your next question is this: how does the universe end?”

“In which dimension? You’re going to need to be more specific; I’ve seen more than one ending.” The Doctor began ticking off options on his fingers. “There’s heat death; the supermassive black hole; the uncontrollable explosive chain reaction between fissile material, a red giant, and a bottle of gentian-flavoured cola; the tragic ravioli incident – really, you don’t want the details, it was most unpleasant – why, there’s even one where the Great Space Whale swallows the old universe and regurgitates a form of ambergris that expands into a new universe. That was rather memorable.”

“Never mind,” grumbled the Great Intelligence. “We draw even again. But I shall still win this competition!”

“You’re very self-confident for an amorphous entity only a question or two away from being ejected into space.”

“Your final question, Doctor!”

“Very well. How much wood could a woodchuck chuck if a woodchuck could chuck wood?”

“That,” the Great Intelligence replied, “is a ridiculous question.”

“Nevertheless, it’s the one I’ve asked, and I expect you to answer it.”

Another long pause. The Doctor imagined the Great Intelligence was rapidly assessing average woodchuck size, jaw and foreleg strength, likely chucking distance, wood gnawed per annum, and wood gnawed over an average woodchuck’s average lifespan, until it finally came to the conclusion:

“This is a rhetorical question! The answer is unknowable! I submit the question is unfair.”

“Life is never entirely fair. Do keep that in mind if you plan on occupying a mortal body.”

“I will not be penalised for your poor attempts at trickery! Admit there is no satisfactory response for this question, or this contest is at an end, and I shall take your brain by force.”

“Oh, you will, will you? All right, I admit it, but you must agree, it was worth a try.”

“Indeed – for if you may resort to questions one cannot possibly answer, then so can I. Prepare to give up your body, Doctor, for you shall surely never answer this: how many pepperoni and anchovy pizzas can I consume in a sitting?”

“And you called my woodchuck question ridiculous.”

“Turnabout is always fair play, Doctor.”

The Doctor harrumphed, but began to work out the calculations. Assuming an entity of vast and almost unknowable size; an estimated 14” pizza; and average quantities of meat, tomato sauce, mozzarella, and tiny fish fillets; how many solar systems’ worth of pizza could the entity consume at one go?

He calculated the minimum and maximum sizes for a stomach potentially distributed across a planet. He factored in the amount of energy such a being might need on a daily basis and converted the number to kilocalories. He integrated over the likely upper and lower boundaries of the numbers, derived a set of curves, refined his equations, derived again.

And then he guessed.

“Five hundred and thirteen,” he said. “And a half.”

The Great Intelligence was silent for several seconds.

“Damn you,” it said.

The Doctor smiled. “Then it’s a draw, which means I get the final question. And if you lose, you leave me be.”

“As promised, Doctor, although my promise may not last forever.”

Jamie punctuated the silence with a massive snort. An idea occurred to the Doctor.

“What’s as big as the universe, burns like fire, dies away but can be rekindled, yet fits inside the body of a man?” He settled back in the bed and waited.

“As big as the universe ...” muttered the Great Intelligence, “... fire ... fits inside the body of a man?”

“Yes, that’s it exactly.”

“It’s not ... wait, it could be ... no, that’s not it, no fire there ...“

“Would you like a hint?” asked the Doctor.


“Well, that’s too bad, because you can’t have one. Do you have an answer for me?”

The Great Intelligence was pointedly, sullenly quiet. “No,” it finally said.

“I thought not,” said the Doctor. “You may leave now. And if you don’t go on your own, I shall ask the TARDIS to make you, and I assure you, she’s more than capable of it. She could have done it some time ago, in fact, but I thought it might be more fun to play a game.”

“I shall not leave without the answer, Doctor!”

“Persistent, aren’t you? Well, that’s as one might expect from a being that lacks emotion and imagination. I expect that’s why you couldn’t solve my riddle.” The Doctor gazed down at Jamie, whose snores had at last subsided into steady breathing. “It’s love, you see. Something you obviously know nothing about.”

If the Great Intelligence had had eyes, it would have narrowed them at the Doctor and made an awful face at him. As it was, it had neither, particularly since it had lost the game.

“You have won this round, Doctor. But perhaps not for all time.”

“Toodle-oo, then! You shan’t be missed.”

A door slammed in the Doctor’s mind as the Great Intelligence whooshed away from him and the TARDIS. No doubt the entity would be sulking in space for some time to come.

Jamie flipped over to face the Doctor, still asleep, his hands pinned below his cheek. And the Doctor slept at last beside his lover, and dreamt of soft-boiled eggs.