Stone and Fire

Ji Guanguan, a young history professor with no strength to speak of, is kicked back into the Paleolithic Age, when people ate raw meat and drank blood, by a mysterious meteorite.

From the start, he has only a pair of glasses (broken), a frame of skin and bones (from hunger), and an immortal body (because he's dead).

Here, he's a "crispy chicken" in the eyes of saber-toothed tigers, an "ant" beneath the feet of mammoths, and a useless weakling to the primitive people, someone who can't carry a load on his shoulders or lift anything with his hands.

"Don't eat me, I've got brains! Really tasty brains... I mean, really useful brains!"

To avoid becoming emergency rations, he has no choice but to turn himself into the "Doraemon" of this prehistoric world.

He teaches the primitive people to build houses (Youchao), so they don't have to sleep on cold, damp ground in winter;

He teaches the primitive people to start fires with a fire drill (Suìren), so they can eat a nice piece of hot, cooked meat;

He teaches the primitive people to record things by tying knots, only for his savage buddies to use the method to keep track of who owes whom two pieces of meat.

He only wants to scrape by in this brutal wilderness, and maybe nudge the progress bar of human civilization forward by just a tiny bit.

But then he accidentally nudges it too far.

Many years later.

When archaeologists of a later age excavate the world-shaking site, they stare at the stone tablet carved with crooked Chinese characters and fall into deep thought:

"Can anyone explain why there's a line saying 'When the odd changes, the even stays the same' in a layer from ten thousand years ago?"