Chapter Ninety-Five: Lightning Mental Arithmetic

What about twenty-five times seven hundred and twenty minus sixty-five?

A voice sounded behind Merton.

One hundred and seventy-nine thousand, three hundred and thirty-five, Merton answered on instinct, only to suddenly realize that the voice of little Li Zhi had changed into that of a grown man. Besides, for a seven-year-old child, the problem was far too difficult.

Merton turned around in surprise and saw Emperor Li Shimin standing behind him, his face dark as thunder.

His heart gave a jolt. The great demon king had truly arrived.

“Your Majesty!” Merton hastily turned and bowed.

“Father!” Li Zhi’s little face went white with fright. Of everyone present, the one he feared most was still Li Shimin, and to make matters worse, he had been caught red-handed tricking Merton into doing his homework for him.

Li Shimin’s expression was grim, as though he were about to erupt.

Li Zhi’s little heart trembled, and he could not help looking toward his final lifeline, Princess Jinyang.

“Father!”

Jinyang’s soft, sugary voice rang out. She came toddling over and threw herself into Li Shimin’s arms.

“Hahaha! Sizi, how did you sneak out again?” Li Shimin’s face changed at once, like an old opera master shifting masks, turning from black to bright with a laugh as he scooped Princess Jinyang into his arms.

“Ninth Brother said he would take Sizi to see the great demon king! He said that once Sizi started school, I would know just how frightening the great demon king is,” Princess Jinyang said in a sweet little voice.

Li Zhi’s face went pale at once. He had been utterly betrayed.

“The great demon king?” Li Shimin glanced at Merton with open disdain, as if to say that if this boy could be called a demon king, then a little catfish would do just as well.

“Your Highness is too kind,” Merton said with an awkward laugh.

“Yes, yes! Your son was only joking!” Li Zhi hurriedly nodded with an embarrassed grin.

With Li Shimin’s arrival, all the princes soon received the news and came streaming out.

“Greetings, Father!” the princes said in unison, led by Li Chengqian.

Li Chengqian stood at the front, while Li Zhi, who had begun his studies latest, stood at the very end. All nine princes were lined up neatly.

From the back, Merton looked at the row of princes standing at different heights and sizes. This did not even include the princes still in swaddling clothes in the harem. He could not help clicking his tongue in amazement, faintly admiring Li Shimin’s prodigious fertility. In an ordinary household, there was no way they could have supported such a brood.

Li Chengqian looked at Merton, blinked, and gave a slight nod. The other princes also turned curious eyes upon this unfamiliar youth.

Merton flashed his usual signature smile, cupped his hands, and bowed. “Merton of Mohist Village pays respects to all the princes.”

“Merton!”

The other princes’ expressions shifted. The chubby boy standing behind Li Chengqian looked excited, while the princes behind him all showed varying degrees of resentment, none deeper than Li Zhi’s.

In his short time at school, Li Zhi had originally thought that memorizing texts was the most painful thing in the world. But after Li Chengqian learned arithmetic from outside, he realized that if he could not remember a passage, he could simply keep memorizing it. Yet if he could not do arithmetic, then no matter how hard he scratched his head, it would still be useless.

In his mind, anyone who could come up with such monstrous problems had to be a demon king.

Inside the Hall of Scholarly Learning, Li Shimin sat upright in formal dignity. Beside him, seated below, was an old man with white hair, who was studying Merton with great interest. Merton smiled and nodded to him in greeting.

The old man paused, evidently not expecting a response from Merton, then smiled and nodded back.

“Lord Wei,” Li Shimin asked, “how are the princes progressing in their studies?”

Merton’s eyes flickered. The family name Wei, and seated before Li Shimin in such a position—there could only be one man with such standing: Wei Zheng.

“Your Majesty,” Wei Zheng replied with a salute, “the princes are progressing very smoothly in their studies. Even the youngest, the Ninth Prince, can already recite The Thousand-Character Classic fluently.”

“Is that so? And what of arithmetic?” Li Shimin asked.

Wei Zheng gave a slight, wry smile. “Your Majesty, the new arithmetic is easy to learn but hard to master. The princes are still feeling their way forward, though with time I am sure they will make great progress.”

In truth, this was already a tactful way of putting it. Aside from Li Chengqian, whom Merton had personally taught, the one who had learned best was the naturally gifted King of Wei, Li Tai. The other princes could be described as a complete mess, especially the mischievous King of Qi, Li You, whose arithmetic was practically nonsense.

“Easy to learn but hard to master?” Li Shimin’s expression shifted. “Just now outside the Hall of Scholarly Learning, I heard Merton answer arithmetic questions without hesitation. Could it be that Merton has not actually tried teaching them?”

At this, Merton felt as aggrieved as a wronged soul. Your own sons have not learned it, and now you say I was withholding my knowledge and refused to teach them?

“Oh? Does County Baron Merton possess such a unique skill?” Wei Zheng said in surprise.

“Your Majesty, it is not that I kept anything from them. This is a lightning mental-arithmetic method, and one must study arithmetic for a period of time before one can begin practicing it.”

“Lightning mental arithmetic? The Mohist school even has such a unique skill?” Wei Zheng said, visibly intrigued.

“Father,” the chubby Li Tai said eagerly, “I would also like to see County Baron Merton’s mental arithmetic. Might I ask him to demonstrate?”

Wei Zheng’s eyes gleamed. “Why not have the nine princes pose their questions in turn, and let County Baron Merton answer them?”

“You have all complained that arithmetic is too difficult. Very well, here is a chance right before you. Give him the hardest problems you can think of, and let Merton answer them. Then we shall see whether the questions are too difficult, or whether you have simply not learned well enough,” Li Shimin said in a deep voice.

“Yes!”

All the princes could not help but look excited. Every one of them was eager to try.

Thus, before Merton had even spoken, the contest was cheerfully decided.

Seeing the princes all busily setting their questions, Li Shimin’s lips curved into a faint smile. Then he turned to the listless Merton and said, “Merton, if you get even one wrong, we shall properly settle the account of your recent affairs.”

Li Shimin bared his white teeth in a threatening grin.

Merton shivered and immediately forced himself alert. There would be no halfhearted effort now. As for offending the princes, that could be dealt with later. For the moment, he had to get past Li Shimin first.

Soon all the princes had finished composing their problems and were looking at Merton expectantly.

Li Zhi went first. Unfortunately, his arithmetic level was limited, and the material he had learned did not go beyond numbers in the hundreds. Though he had done his utmost and posed a mixed addition-and-subtraction problem with five-digit numbers, Merton blurted out the answer the very instant Li Zhi finished reading it.

“Correct,” Wei Zheng said, moving his counting rods and giving a nod.

“Ah...” Li Zhi said, his voice heavy with disappointment.

The other princes now looked on with great interest. Such a troublesome calculation had been rendered absurdly simple in the mouth of this young man from the Mohist school.

Lightning mental arithmetic truly was no ordinary thing.

The remaining princes then racked their brains to set their questions, yet none of them managed to trouble Merton in the slightest.

Soon, the third prince, King of Wu Li Ke, also failed. His problem was a mixed operation of addition, subtraction, multiplication, and division involving ten digits.

Three hundred and twenty-four.

Within three breaths, Merton gave the answer.

“Wow!”

The princes cried out in shock.

Three breaths’ time, and he could not even have finished writing the question, yet the young Mohist had already produced the answer.

“How can he be this fast?” Wei Zheng was stunned, staring at the counting rods he had only just moved three times.

Even Li Shimin’s eyes now shone with brilliance.

“County Baron Merton’s arithmetic truly has its own extraordinary merits. I am impressed,” King of Wu Li Ke said respectfully.

“Your Highness flatters me. I merely rely on the convenience of calculation,” Merton replied modestly at once.

He was also deeply interested in this tragic prince. Li Ke carried the blood of both the Sui and Tang royal houses; one could say he possessed the noblest lineage under heaven. Yet that noble blood was also his deepest original sin, and in the end he died under false accusations.

“Young King Li Tai greets County Baron Merton,” said the chubby boy in a refined and courteous manner.

“Greetings, Your Highness, King of Wei,” Merton replied. He did not dare underestimate this famous figure from history. According to the records, King of Wei Li Tai was a textbook academic prodigy.

Born well and diligent besides, he practically crushed all the other princes flat. No wonder Li Shimin favored him so deeply, even to the point of threatening Crown Prince Li Chengqian’s position.

“Ah, Qingque is serious now,” Li Shimin murmured to himself. No one knew his sons better than he did. From Li Tai’s expression, he could tell that the boy was surely holding back something big.

As expected, when Li Tai revealed his problem, the whole hall broke into an uproar. His question contained only two numbers, two absurdly long numbers to be divided.

One hundred fifty-eight million, seven hundred sixty-five thousand, nine hundred thirty-seven thousand, one hundred eighty-two divided by six million, one hundred eighty-four thousand, nine hundred fifty-five.

The room erupted in commotion. How was anyone supposed to calculate such a long division problem?

All the princes looked at Li Tai with admiration. As expected of Second Brother—now let’s see how that boy from the Mohist school figures this out.

Wei Zheng stared at the counting rods in his hand, bewildered and at a loss as to where to begin. Li Shimin, meanwhile, watched Merton with keen interest, hoping to catch even a trace of panic in his eyes.

Twenty-five thousand, six hundred sixty-nine point six nine.

Only five breaths later, Merton suddenly lifted his head and gave the answer.

“Wow!”

“How is that possible?”

“How could he work it out so quickly?”

The whole hall burst into uproar.

Li Shimin sprang to his feet, staring at Merton in utter disbelief.

“Second Brother, is Merton’s answer correct?” King of Wu Li Ke asked, unable to believe it.

Li Tai’s face twitched. “If I said I just made up the question at random and I don’t even know the answer myself, would you believe me?”

In the end, Li Chengqian and Li Tai spent a quarter of an hour calculating it before they finally obtained the result to that monstrously long problem.

“The answer is correct!” Li Chengqian said, looking down at the result in his hands as he let out a long breath.

At once the entire hall went wild, everyone staring at Merton in astonishment. Such a huge calculation, solved in such a short time—lightning mental arithmetic was simply divine.

Merton laughed inwardly. This was nothing. They had never seen the contests on certain radio programs in later generations, where the problems were truly monstrous and the atmosphere on site was far more feverish than this.

Merton had defeated eight princes in succession, leaving only Crown Prince Li Chengqian.

Li Chengqian looked at the question in his hand and sighed. “All my arithmetic knowledge was taught by County Baron Merton. I shall not make a fool of myself. I concede defeat.”

Thus, the record stood: Merton versus the nine princes.

Nine victories out of nine.