Chapter 9: Through New Lenses: The Dawn of Cosmic Truth

I wasn’t personally grinding lenses or assembling telescopes—that was the job of the lens crafters. Nihir introduced me to the guild of crafters she regularly worked with, and I handed them designs for convex and concave lenses to produce.

Existing telescopes used two convex lenses, but a Galilean telescope incorporates a concave lens. For skilled crafters, making a concave lens isn’t difficult, but the key lies in the concept itself. The realization that a concave lens is needed to improve a telescope and expand the field of view—this understanding of underlying principles was what this medieval world lacked, preventing the creation of better telescopes.

Not long after ordering the lenses, Nihir informed me that the finished products had arrived. In her office, she handed me a silk pouch containing the lenses. With curiosity in her eyes, she asked, “Mr. Aren, how do these lenses make the telescope better?”

“It’s better to show you than to explain.”

Her office conveniently had a primitive refractive telescope with two convex lenses. Peering through the eyepiece, the world appeared blurry and inverted, like a moon shimmering on water. “Current telescopes use two convex lenses to magnify objects, but the image is inverted, and differences in refraction reduce clarity. Replacing the eyepiece with a concave lens…”

I removed the lenses and replaced them with the ones I’d ordered. Looking through the eyepiece again, the world was sharp and clear. The image was upright, with vivid colors and details. “A concave lens has the opposite property of a convex lens—it diverges light. Using a concave lens as the eyepiece corrects the inverted image from the convex lens, allowing us to see a clearer, sharper world.”

“Can I try?” Nihir asked.

“Of course.”

With a childlike expression of anticipation, Nihir brought her right eye to the eyepiece, closing her left. “Wow, it’s like seeing a new world! It’s so clear and vivid. I can even see the tiny hairs on distant leaves! This is incredible!”

Her excitement was understandable. The Galilean telescope boasted up to twenty times the magnification of existing ones, a revolution for human vision. It could reveal the moon’s craters, Jupiter’s moons, and sunspots—exactly the effects I wanted. Gradually advancing this medieval world was indeed the right approach.

If I’d introduced a Newtonian reflecting telescope right away, the impact wouldn’t be limited to astronomy. Medieval people suddenly noticing bacteria or cells? That’d cause chaos. “This is a groundbreaking idea—overcoming the limitations of existing telescopes by changing the lens combination. Why didn’t anyone think of this before?” Nihir asked.

“It’s just applying nature’s principles. Using the properties of light and finding ways to harness them.”

“With this telescope, we’ll see a world we’ve never seen before. I’m so excited!”

“Now we need to spread this telescope as widely as possible. It uses the same materials, just differently shaped lenses, so it shouldn’t cost more than existing ones. It’ll replace them quickly.”

“I can help with that. I’m close with the lens crafters since I work with them often.”

“Can I count on you, then?”

Nihir nodded firmly, awestruck by the telescope’s power. “Yes, trust me. I’m thrilled to help you, Mr. Aren. These telescopes will sell like crazy. They’ll make you rich!”

“I’m not trying to get rich. We shouldn’t profit excessively. The goal is to get these into as many hands as possible.”

Nihir’s face lit up with admiration, her deep blue eyes reflecting my idealistic goal. “Of course. Our aim is to prepare the world for heliocentrism. This telescope will play a key role.”

Nihir explained the new telescope’s principles to the lens crafters’ guild, crediting me and detailing how the combination of concave and convex lenses magnified and clarified images. “The materials are the same, and the process isn’t much different, so costs should be similar.”

Initially skeptical, the crafters were stunned after building one as instructed. It was dozens of times better than old telescopes—there was no reason to make the outdated ones anymore. “We’ll produce all future telescopes this way. Thanks to Mr. Aren, telescopes have advanced so much!”

My new telescope shook the world in no time. People were captivated by the wonder it brought. It permanently changed how they saw the night sky. After my compromise theory sparked interest in the cosmos, the telescope ignited that powder keg. News of its superior magnification spread through the capital.

People yearned to witness the sky’s mysteries firsthand. The lens crafters’ guild had to hire hundreds more apprentices to meet demand, and buyers crowded their shops. Nobles prioritized these telescopes over expensive jewels, and merchants supplying them made fortunes overnight.

The city’s nightlife transformed. Telescopes gleamed not just on mountains but on rooftops, creating a terrestrial Milky Way. Countless people gazed through my telescopes, awestruck, their eyes filled with curiosity and passion.

“Look at that! There are craters on the moon!”

“It’s true. The moon feels alive!”

People marveled at the telescope’s world, thrilled by the moon’s craters and sunspots, stepping into an unknown realm. The mysterious cosmos began revealing itself to ordinary people previously uninterested in celestial motion. Astronomers’ reactions were even more fervent, making repeated discoveries and stirring a new wave in academia.

“It’s true—Jupiter’s moons orbit Jupiter!” one astronomer shouted, unable to tear his eyes from the telescope. He passed it to colleagues, raising his voice in excitement. “I can’t believe it. Look! This could overturn everything we know about the universe!”

Astronomers recalled the line at the end of my paper: “Perhaps the center of the universe is neither the Earth nor the sun.” A shiver ran through them, as if touching a forbidden taboo. The telescope’s revolution created the potential for a massive ideological shift in this medieval fantasy world. People were now confused by old beliefs and ready to embrace new truths.

My telescope was more than an observation tool—it was an instrument of enlightenment, igniting human consciousness. I sensed the world was ready for a new era. Beyond the horizon, the faint shape of that era turned toward me, holding a torch of reason to illuminate a dark world.

‘I’ll announce heliocentrism at the next astronomical society meeting.’

With that, I decided to turn a page in history.

Lucia sat at her desk, her pen dancing over paper. The argument with me swirled incessantly in her mind. An undergraduate acting like he could teach her? No matter how she thought about it, it infuriated her. “An undergraduate spouting nonsense about the Earth not being the universe’s center!”

She couldn’t accept such absurd claims. Clenching her teeth, she shouted in her room, “The Earth being the universe’s center is the truth! All celestial bodies move in perfect circles around it!”

Ptolemy’s cosmology had endured for a millennium. Its unshaken longevity proved it was an immutable truth. The Earth sat at the universe’s center, orbited by the moon, Mercury, Venus, the sun, Mars, Jupiter, and Saturn, as the great scholar Ptolemy declared in Almagest, conquering the cosmos for humanity.

Recalling this system, Lucia drew intricate circles on her paper. Ptolemy introduced epicycles to explain celestial motion—perfect circular orbits around the Earth. “Yes, this way, I can explain Mercury’s retrograde and Venus’s phase changes, just like Aren’s new theory!”

Under a faint candle, Lucia drew an insane number of circles, like a madman’s work. Countless epicycles moved along a central deferent—hundreds at a rough count. To her, Aristotle’s cosmology was truth: the terrestrial world was imperfect, but the celestial realm was perfect and unchanging, so all orbits were flawless circular motions.

Unable to abandon this outdated notion, Lucia drew increasingly complex circles. “This is the truth! The perfect universe created by God!”

She toiled through the night, crafting equations and shapes, obsessively explaining celestial motion within geocentrism. Sometimes she added epicycles to epicycles. A paper emerged. “This will crush Aren completely.”

She recalled that I had applied to present at the next meeting. ‘I’ll present this right before Aren. I’ll criticize him harshly during my talk. He’ll be too humiliated to speak!’

The thought was exhilarating. A smile crept onto Lucia’s face. Though exhausted, her dark eyes brimmed with confidence. I had challenged the truth and would fall miserably.

Approaching the window, she saw dawn’s twilight outside. She peered through the telescope her parents had bought her, now called the “Aren-style telescope.” People praised me for revolutionizing telescopes, but Lucia hated even the name. She vowed to develop a better “Lucia-style telescope” to erase mine.

It was expensive, but her family was wealthy—astronomy wasn’t for the poor in this medieval world. “Ugh, it does work annoyingly well,” she admitted.

As the sun rose over the horizon, the world bathed in fiery red. It was already proven that the sun was far larger than the Earth. Gazing at this majestic, overwhelming sight, Lucia felt a chill sweep over her skin.

‘No… no way. It can’t be. A truth that’s lasted a millennium…’