Chapter 8: Lecture

“A monster flood is when monsters who inhabit regions around ley lines form a pack and attack the open plains; in other words, human territory. Over the course of history, the greatest and first recorded monster flood occurred approximately four hundred years ago.”

Fulsig continued his introduction in front of the slate board supported by what looked like two large easels. The history of the founding of the nation was something we were familiar with as well.

“The ‘Great Flood,’ right? I believe it’s said the old monarchy that was here before Crownheight was destroyed by it,” I replied.

The monarchy that was said to have been destroyed four hundred years ago was at least as large as both the current Empire and Kingdom combined. Incidentally, both countries claim to be the true successors to said monarchy.

The way Fulsig phrased it as “the greatest and first recorded” such flood likely meant that records of floods before that were lost to the Great Flood and the chaos that ensued afterwards. That also implied just how wide a range the flood back then covered. It’s been said that dragons covered the entire sky at the time.

“A flood on that scale has not occurred again, but small-scale floods have occurred to the east about once every five years, and medium-scale floods about every ten years. As for the cause of the floods...”

Fulsig pointed at the right side of the map, where the eastern mountain range was. The mountain range had symbols drawn on it over several locations.

“It’s the fluctuation of the ley lines. The source of energy for monsters is miasma, mana with a clouded color which wells up from the mountain range. Consequently, one could say that the structure of the mountain range itself dictates the flow of the ley lines. As you can see, the mountain range to the east has a very complicated structure.”

Taking a closer look, there were red lines drawn over the eastern mountain range, and the symbols were placed atop locations where the lines intersected. I see, so the mountains are like rivers where mana flows instead of water? From the way he said mana “wells up,” the fact that mana is stronger in the mountain ranges than on the open fields is a bit of a contradiction, isn’t it?

Wait, what if we think of it like a mantle floating on the earth? A good example would be ice floating on water. The further up the ice sticks out of the water, the deeper into the water the other side goes. If we think of mana as something which wells up from the core deep down...

Now isn’t the time to be thinking about geology, though. First, I need to worry about what’s happening above ground. Grasping the relation between ley lines and monsters is the vital point here.

“It’s just like a river, you could say. There are times when the flows of mana cancel each other out and stay calm, and there are times when they pile on top of each other and become stormy. And this affects the monsters who feed on mana. Putting it simply, the more mana there is, the more monsters there are. When the increase in mana tapers off, the monsters starve. As a result, they rampage towards the open plains. And that’s how monster floods occur in the present day.”

Both here and on Earth, humans and other creatures relied on energy from the sun as a foundation for activity. However, monsters also depended on the energy from mana, which came from below ground. Even back on Earth, there existed ecosystems deep under the water that didn’t depend on the sun. They got their energy from heated mineral deposits at the bottom of the ocean.

“The monster floods consist of a pack of grausams. It’s said that their habitat is deep in the mountains. Larger and more powerful monsters depend on a proportionally large amount of mana, and it’s thought that the smaller monsters, who increase in population greatly due to their small dependence on mana, are hunted by the grausams.”

Grausam would be the name of that huge wolf whose severed head I saw once before. It was originally an inhabitant of Earth, and its growth to such a massive size over just a few years was perhaps thanks to its hybrid source of energy over here. I took a glance over to the data Mia had in her hands. This was a point that needed confirmation.

“Now, let’s look at the west. The western mountain range is relatively simple compared to the east. It’s not possible for large fluctuations of mana to occur like it does in the east. In fact, all recorded monster floods in the Kingdom have been from the east.”

Fulsig pointed at the opposite side of the map. The mountain range ran in a single line from north to south while only meandering about slightly. I get it now. So in terms of the flow of mana, the west is far more stable.

“So, how’s that? Is this what you wanted to know?” Fulsig’s eyes were practically asking me, “Now what will you do?”

So that’s the mechanism behind monster floods. His explanation makes perfect sense now. As long as the disaster is happening in the west, the probability of a monster flood is quite low. From that perspective, it’d be better to abandon any fixation on my own idea and deny it along the same lines as a regular flood or a volcanic eruption.

Alfina looked at me with a troubled expression. If we were able to amend the probabilities, we could discard the hypothesis and move to the next. I wasn’t lying when I said that, but...

“I do have one question. Monsters don’t only feed on mana, right? They also eat regular flora and fauna?” I cut right to the question I had prepared beforehand.

“Mhm. The victims of monster floods were all found nearly completely devoured. The same goes for livestock such as cows. However, it’s a definite fact that mana is a necessity to them. In fact, before we could predict monster floods like we can today, the grausams were dealt with by waiting for them to exhaust all their mana rampaging about before engaging them.” Fulsig grimaced slightly as he continued his explanation. There must’ve been a tremendous number of victims. And if our hypothesis is correct, that’ll apply to this case as well.

“Understood. Could we borrow the slate board? Mia, please explain the data we have.” I passed my instructions to Mia, and our presentation that we had prepared at the cost of our own work began.

“Due to the stability of the Kingdom’s climate, the temperature in the area between the east and west is largely the same. The only environmental condition with a certain degree of difference is the precipitation, and the crop yields line up well with the rainfall. The correlation coefficient between them is 0.86.” Mia fixed two hand-drawn graphs to the slate board as she began her explanation.

“What’s a correlation coefficient?” Fulsig tilted his head at the statistical term he was unfamiliar with. Alfina, on the other hand, looked like she had no idea what was starting.

“Putting it simply, it’s a quantification of how strongly two trends are related to each other. What’s shown here is the crop yields and the precipitation. It demonstrates the relationship between the rise in rainfall and the respective rise in the harvest.” Mia pointed her finger at one of the hand-drawn graphs.

The horizontal axis represented precipitation, and the vertical axis represented the crop yields. Each point represented the average yield across the specified region. The graph rose to the right. A region blessed with more rainfall fundamentally yielded more crops, since there was never any rainfall here severe enough to cause flooding. The climate was just that stable.

“It can be calculated with this manner of simple numerology.” Mia wrote down a simple equation on the slate board. Incidentally, this country referred to arithmetic, or all mathematics in general, as numerology.

Fulsig stared at Mia’s equation intently. The formula for the correlation coefficient was actually quite simple. Well, there were some numerical formulas I taught Mia that she called simple, but they were actually quite difficult for me.

“...What an interesting method of calculation. It makes sense. However, can this data on crop yields really be trusted? No matter how many calculations you make based on incorrect numbers, you’ll only amplify the mistakes.”

Crop yields were closely related to taxes. Meaning, it was something that nobles often try to falsify. On that note, what Fulsig just said was quite politically dangerous.

Mia glanced at me. She was confirming whether it was okay to tread here, and I nodded back at her. If he went so far as to bring it up, then we just have to respond in kind.

“It’s unreliable for the noble territories. However, even in the sense of simply keeping the nobles in check, the crop yields in territories managed by government officials of the Kingdom’s duchies can be trusted. This is also made obvious from the variance in the crop yields.” Mia pointed at a second piece of paper.

This graph showed the yields reported by noble territories and those of the duchies, noted by dots as a distribution from the mean. The duchies’ points for crop yields formed a curved line, meaning they had a normal distribution. On the other hand, the yields from the nobles plateaued into a flat line. You could say they were distorted by some external cause, and by that I mean the nobles’ whims.

“The variance of the crop yields in noble territories is unnatural, whereas the variance of the duchies’ yields is very close to natural. This result is demonstrated by the following equation, and there is a clear difference between the two. As such, the data this time around was collected only from the duchies.”

This data was basically a bombshell, since it was closely tied to optimizing the investigation of tax evasion. Incidentally, this data was something we largely already collected over a week ago. There were two reasons for that.

The first one was to prepare the last-ditch weapon we needed in the fight against the Dreyfans in the future, since the one good the Culinary Guild handles the most by a large margin is wheat. The reason it was a last-ditch weapon was because we also wouldn’t get away from it unscathed. So if possible, it would be best if we didn’t have to use it.

The second, and far more important reason, was to get an understanding of changes in agricultural productivity across the nation. After all, the most fundamental question behind economic development is, “how many people does it take to produce one hundred people’s worth of food?”

“How interesting. It’s expressed as a difference from the averages, but when you put it together it becomes... Hang on, what if we take this concept and turn something that should be a coincidence into a numerical formula...?” Fulsig was completely drawn into the calculations.

He even began diving into the concept of statistical significance before Mia could explain it. So his senses for grappling with numbers for decades when he analyzed the ley lines are still active? In any case, he certainly seems to fall completely under the category of a genius.

“Let’s return to the topic at hand. Dividing the east and west, we can see that the correlation coefficient of the western region is 0.88. Ergo, the rainfall and crop yield almost coincide with each other. In contrast, the eastern region’s coefficient falls to 0.7. This is because there are years of ‘slightly abundant’ harvests which don’t match the rainfall. As for their latest occurrences, going by the Kingdom’s calendar, they were in 347, 342 and 334. The crop yields during these years were higher than what should be estimated from the precipitation.”

Going by today’s date, that would be 3, 8 and 16 years ago respectively. And those years all had one thing in common.

“The years monster floods occurred in the east, eh?” Fulsig concluded.

“Precisely. According to Princess Alfina’s prophecy, an abundant harvest is to be expected in the west. But on the other hand, there won’t be one in the east. This means that both the prophecy of disaster and the prophecy of abundance may support each other.”

Fulsig groaned slightly at Mia’s explanation, and Alfina gave us a shocked look. We were also surprised by this result. The data, which ran counter to intuition, was actually hiding something quite tremendous behind it.

“Let’s go back to talking about the past first. Factors which influence crop yields irrespective of climate only exist in the east.” This was where I came in. I stood up and spoke to Fulsig, as he despairingly stared at Mia’s equations. “In those three years, the knights crushed the monster flood before it could break out. And nevertheless, the crop yields increased. Why is that?”

Fulsig turned to face me. All the better, now that he was ready to deal with me.

“The important point is the geography. Actually, the abundant harvests we just spoke of...” I affixed a third graph to the slate board. The lines and writing on it were clearly messier than the other two. “They’re stronger towards the very eastern edge. In short, the villages closest to Loewer Wald show a remarkable trend. So, let’s go back to my initial question. Monsters also feed on regular animals; ergo, the fluctuation in the monster population has an effect on the animals in the adjacent region. Right?”