“Isn’t it common knowledge that the world is made up of elements…?”

 

That was the response of a great sorcerer who had lived his entire life in a medieval fantasy world.

 

“But that doesn’t make sense. If the fundamental unit of all things isn’t elements… Then what about elemental magic? Fireballs and ice spears? Why can some sorcerers handle fire magic effortlessly but are utterly incapable of earth magic?”

 

Naturally, my answer was ‘I don’t know’.

 

Magic was, after all, a concept that existed only in the imagination on Earth.

 

Had I been a former physics PhD, perhaps I might have had a shot, but an ordinary office worker like me using the power of modern science to intuit the underlying principles of magic? That hadn’t happened yet, nor was it likely to happen.

 

The master of the magic tower, who looked as if he had just been told the world was actually made of chocolate, offered a calm rebuttal.

 

“Besides, the laws of physics could vary across different worlds. Just look at the spirit realm; it follows completely different laws from our continent. Isn’t it possible our world doesn’t operate like that?”

 

It was a sharp observation indeed.

 

“Our universe flies,” as they say.

 

The common knowledge of Earth might not apply in another world, especially one in which magic exists.

 

Where gods and demons seem to exist, and clerics and demon-summoners directly draw power from them.

 

This world could be different—it could have a flat land, or perhaps the universe isn’t insanely vast but rather small and intimate, the size of a planetary system.

 

I considered it a possibility and refrained from jumping to conclusions too soon.

 

So I conducted experiments. I wanted to see how far the scientific common sense of Earth would apply in this other world.

 

“Most of it was correct.”

 

“Really?!”

 

“Of course, I’m not from a research background. So, I could only test simple things.”

 

I’m talking about the famous experiments you’d find in a science textbook. Using a stick’s shadow to determine whether a planet is round, detecting cosmic microwave background radiation, causing crystals to grow on a stick.

 

Some experiments were a struggle due to difficulties in obtaining materials, but the grants coming into my magic tower were supreme and godlike.

 

Excluding the ones involving magic-infused materials like mithril, scientific knowledge had a series of unbroken victories.

 

They could conclude that the continent was a round planet.

 

“The continent wasn’t flat…!!”

 

“By calculations, it’s a planet with a radius of about 7,500km, but I did this out of boredom, so it’s not accurate.”

 

“The end of the sea wasn’t just a cliff and an infinite void…”

 

After my reincarnation in a parallel world, during the time when I farmed potatoes in the countryside with my parents,

 

I heard such stories from the neighborhood priest while sharing bread.

 

Something about the gods of darkness and light collaborating to create humans and so on.

 

In the middle of that story, it was said that the earth is flat and that if you sail out to sea, you will plunge into the void.

 

The magician seemed to have much to think about and held his head, groaning. It seems embarrassing to have his common sense directly refuted.

 

I felt the desire to pour modern knowledge into that tiny head and cause a scientific corruption, but I was patient. After all, I’m not a scientist but a fantasy wizard who likes TRPG.

 

In fact, whether the Earth was flat or round was not the important part.

 

We had to focus on a slightly different point.

 

“I’m not sure if it’s really like that, or perhaps I’m mistaken, but regardless it’s interesting, isn’t it?”

 

“…Huh?”

 

There is an illusionary spell that summons butterflies here.

 

The illusionary magic created by a child who has never seen a butterfly and that created by an adult who has been raising butterflies for decades has a vast difference. The adult wins.

 

The power of an illusion increases according to how detailed it is, and to what extent you believe in it.

 

This is the same even when summoning the illusion of a single knight.

 

The mere ‘guard at the castle gate’

 

Can’t win against ‘the gatekeeping knight, who has had a childhood friend in his hometown for a long time, currently flirting with the blacksmith’s daughter, but recently his childhood friend moved to town and started living next door, causing trouble.’

 

In other words, settings matter.

 

“Can’t we put it to use in illusion magic?”

 

“Uhmm…”

 

The more you think, the stronger the illusion. As an illusion magician, the magic I pioneer might also be

 

From Noble mtl dot com

 

Because such knowledge enables a wide range of settings.

 

The whole world is subject matter.

 

You can even extract TRPG material from the rain droplets flowing on the window.

 

Even with a single knock sound from your neighbor, all genres from thrillers to romance sprout.

 

I wanted to feel the thrill of modern knowledge, ‘Is this what you don’t know, this is such and such…’

 

But more than that, I wanted to give the purple magician something interesting to talk about.

 

“So instead of making a headache expression, how about thinking of it as getting an interesting material?”

 

“But, still, isn’t it scary that the universe is so big, don’t you feel like your life is all meaningless…?”

 

“Doesn’t it make you excited that humanity has a lot of places to explore? Come on, let’s go to the biology corner next. I have a lot of things I want to say.”

 

————-

 

This damn medieval era was the most problematic because of its dirtiness.

 

They didn’t know the existence of germs, so they washed occasionally and ate carelessly…

 

Every day, they scolded me for being weird when they saw me washing at the stream.

 

But now it’s time for revenge.

 

I will unleash the poison of hygiene management in this medieval fantasy.

 

“This is a microscope. It’s a device that can magnify small things.”

 

“…And?”

 

“This is the underwear of the purple mage tower lord. Do you use clean magic once in a few days?”

 

The purple mage tower lord looked like he was wondering if he should tear apart this impudent illusion with this world. But when I came out with a thick skin, he seemed to think that there must be some reason.

 

He was embarrassed, but he didn’t know why he was embarrassed, and he answered with a face.

 

“…Well, for now, once a week.”

 

I slapped my forehead at his answer. And I set the panties on the microscope slide and told him to take a look at his own sin.

 

The mage tower lord tilted his head and brought his eye to the microscope, and he jumped. Like a cat that suddenly found a cucumber.

 

“Uh, ugh… Gross, what are these slimy blobs that wriggle weirdly…?”

 

“Ah, you don’t know── that is.”

 

“Sp, speak properly.”

 

The mage tower lord gathered a terrible force on his finger, and I became polite.

 

“That is a microorganism. It means a small creature, literally.”

 

“…You, you’re not trying to fool me. They’re really out there, right? These things.”

 

“Yes. Things like colds, itchy skin symptoms, runny nose and fever symptoms, etc., when your body is sick but not cursed, are all because of germs. They are the bad guys among the microorganisms.”

 

“Germs…”

 

“These guys breed in dirty places. On unwashed skin, on unwashed clothes, on uncleaned laboratories…”

 

“……!!”

 

The mage tower lord was startled and shook off his clothes with his palm, as if he had bugs on him.

 

But there was no way that things that were invisible to the eye would fall off.

 

“You seem to use clean magic on your clothes when they start to smell a little. By then, they will be bubbling. Bubbling.”

 

“Don’t use such expressions…!!”

 

“This is why you should wash every day. And it’s the reason why you must wash your hands frequently too. It’s not that I’m overreacting, it’s that you all are filthy -“

 

“Got it, I said I got it!”

 

The purple tower master grimaced in sincere disgust and squirmed constantly.

 

Like becoming conscious of one’s own breathing, only to be unable to forget until it becomes second nature.

 

Now that he was aware of the tiny critters crawling on his skin, it seemed to bother him a great deal.

 

I can be certain. The ranks of the clean members of the tower has just increased by one.

 

“I wish I hadn’t known.”

 

“If you hadn’t known, you’d continue to be filthy.”

 

“Don’t tell a lady she’s filthy!”

 

“Shall we go see the war weapons next.”

 

————-

 

We connected a computer to the cinema screen to view the footage.

 

Guns.

 

“…You can use it without knowing magic, right? Like this, it seems like ordinary people might fight more often…”

 

“Doesn’t it feel threatening? Imagine if all the peasants of a territory were armed with guns for war.”

 

“A single blast of the Golden Tower’s ‘Metal Distortion’ would turn them all to scrap metal, wouldn’t it…?”

 

Indeed, guns don’t seem that threatening after all.

 

In a world where human effort could turn someone into a walking main battle tank.

 

Then, what about missiles?

 

“A mage stationed there could defend against it, but if they were mass-produced with intent…”

 

Nuclear weapons.

 

“…By any chance was the world you lived in filled only with mad wizards who wanted to bring about the end of the world?”

 

“Um…”

 

“Logically, a weapon that could turn everything to ashes by mistake is almost the same as a dark magician attempting to resurrect an evil god, right?”

 

“That’s right, isn’t it?”

 

“But then… because the neighboring country could potentially resurrect an evil god, we would prepare to do the same, just in case… Is that what happened?”

 

“That’s… right?”

 

“Was the world you lived in filled only with mad wizards who wanted to bring doom upon the world?”

 

Upon further reflection, I couldn’t deny it.

 

The madness of humanity; was it to such an extent that even those from another world would question if we were all insane sorcerers?

 

“If the development of something called science leads to this, then perhaps it’s better for everyone to live in ignorance…”

 

The tower master muttered as if he had just witnessed a terrifying giant octopus.

 

Before the archmage could cook up a policy of willful ignorance in his mind, I guided him to the next spot.

 

“Finally, let’s go to the place where I used to live.”

 

“The place you lived?”

 

“Yes. It seems the last part will be about my past. Would you listen to it?”

 

The tower master nodded.

 

Just to make sure, I asked again.

 

“If it seems boring, we can skip it.”

 

The tower master playfully tapped my head with a ladle conjured from illusion.

 

It seemed to mean ‘don’t hold back, just spill it,’ and so, I laughed.