“When you only remember the formulas on the surface, anyone who can recite more than you can make you feel utterly defeated.”

“Why? Because in truth, you know nothing at all.”

“If you can recite formulas, all you see are those broken characters and the admiring looks from others, but in reality, these…” Old Carter poked at the entire wall, then pointed single-handedly at the sea of stars above their heads, “are that.”

“The stars?”

David Carter murmured, then received a flick on the head from her dad.

“Please call it the universe.”

“Oh.”

If the kids were to ask what the universe is next, this story would never end. Clearly, as it was close to nine in the evening, most of the children had little patience to listen to a spirited young man talk about the universal truths behind every formula.

So by the time Old Carter got to the Pythagorean theorem, most of the crowd had dispersed.

Old Carter was still speaking enthusiastically, but when he snapped back to reality, only the little boy who had been crying earlier was left in front of him.

David Carter squatted by the door watching them, yawning.

Old Carter then tossed aside the chalk and began his concluding remarks: “In summary, just being able to recite formulas is meaningless. At your age, you can’t yet understand their true meaning, so what’s wrong with me telling a few interesting science stories?”

David Carter: “……”

Little boy: “My… my dad says… I have to memorize them.”

“What your dad says isn’t as right as what her dad says.”

At that time, she was already so sleepy she could barely stay upright, but she vaguely remembered Old Carter pointing at her and saying proudly.

All in all, in her memory, this was a rather absurd story.

Old Carter was high-spirited, always grabbing kids for brainwashing-style science education.

And she was still very young, with a long and boundless road of possibilities ahead of her.

Not like now…

Not at all.

Her phone vibrated, pulling David Carter back to reality.

She lit up the screen. There was a WeChat message.

Little Harris — [My dad knows the director of neurology at the Sixth Hospital. We’re having dinner together tomorrow, I’ll introduce you.]

Clutching her phone, she lifted her gaze and took a deep breath.

In front of her was a wooden door. She bent down, picked up the chalk from the floor, stepped forward, and wrote down the first formula that Old Carter had casually written on the wall that year.

E=MC2 (squared)

Chapter 7: The Beginning

Suppose…

Suppose David Carter had known in advance that by taking this step, she would encounter such bizarre and absurd things.

Then before all this, she would definitely have looked up the winning numbers for the sports lottery that year and memorized them by heart.

But she didn’t have the chance—after all, no one knows they’re about to time travel before it happens.

That’s right. According to the broad definition in online novels, after she finished writing the entire formula, she returned to the age of twelve.

She was still holding the chalk, in the same posture as when she was writing on the wall.

But the wall was not that wall, the door was not that door, and even the stray cat by the roadside was not the same little tabby.

The surroundings had changed completely.

David Carter took half a step back, carefully examining her now shorter, darker, and chubbier arms.

“Shit.” She cursed, stared at the wall, and fell silent.

The wall was made of red bricks, with a huge iron gate on the right.

And on the upper left side, there was a metal plaque. Its color was old, tinged with verdigris, and it read “Anning City Project Hope Sponsoring Unit.”

She didn’t know what had happened. Dully, she shifted her gaze to the left and saw more plaques.

Some were yellow, some white, some new, some old.

Some read “So-and-so University Social Practice Base,” others said “Heart-to-Heart Mutual Aid Pilot Unit.”

The last plaque was the largest, with black characters on a white background, reading—“Anning City Hongxing Welfare Institute.”

Strangely enough, though after returning to the past this little oddity was nothing—at that moment, she was acutely aware that she was still herself, only she had returned to the year she was in fifth grade.

It was as if someone had tapped her forehead, and information flooded in, becoming part of her consciousness. She accepted it all quite naturally.

She even knew clearly that the welfare institute behind the iron gate was called Hongxing, and it was where she had lived day and night for the twelve years up to fifth grade.

She had been abandoned here as a child, with no parents and a strange temper. Fortunately, she was good at her studies, and the director-mother liked her and even managed to send her to a regular elementary school in the district.

Although her life path was now completely different, she was still the same David Carter.

Only this time, she had neither a mother nor a father.

The change was so sudden that, even with an adult’s mind, she still felt a helplessness and confusion she had never known before.

Her legs went weak, her heart pounded, and she couldn’t help but sit down on the steps at the entrance of the welfare institute.

After sitting for a while and calming down, a flash of inspiration came to her. She finally found a phrase she’d once heard to describe her current situation.

—Every choice a person makes creates a different world.

It’s just like standing in a cake shop, torn between choosing strawberry or cheesecake.