What is the 500 Million Year Button?

A thought experiment from a Japanese short manga by Sota Sugawara. Press the button and you receive a cash payout. In exchange, your consciousness spends 500 million years in an empty space where you cannot die and cannot sleep. When the 500 million years end, every memory of them is erased and you return with the money. The original sets the payout at one million yen; this game uses five million.

Do I have to wait 500 million years?

No. Using time acceleration and the card progression, a first playthrough takes roughly seven to nine hours of real time. Progress auto-saves, so you can play it across several sittings.

Is the game in English?

Not yet. The text and voice acting are Japanese only. The game is still worth looking at for the 3D scene and the structure, but the writing is the point of it, so an English release is something I would like to do.

Why is the first load slow?

The build is about 27MB. Audio is streamed in scene by scene rather than all at once, so only the first load is heavy. It may look frozen. Do not refresh, just wait.

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Press the button. Then watch what happens next.500 Million Years

Clicker Thought Experiment Japanese Only

Language note: this one is Japanese only, text and voice. The 3D scene and the structure carry across, but the writing is the whole point of the game, so an English version is on my list.

There is a button. Press it and you get five million yen. The catch is that the moment you press it, your consciousness goes somewhere with no light, no walls and no exit, and you stay there for 500 million years. You cannot die and you cannot sleep. When the time is up, every memory of it is erased and you come back holding the money.

That is the 500 Million Year Button, a thought experiment from a short manga by Sota Sugawara, and most people who hear it end up arguing about it. If the memory is erased, is it free money? Or is it still unmistakably you who lives those years?

The original sets the payout at one million yen. This game raises it to five million, which does not change the argument so much as make it harder to wave away.

This game does not answer that. It shows you the part nobody talks about: what a mind actually does with 500 million years of nothing.

At a Glance

Genre	Observation clicker, idle game, narrative
Price	Free, no install, no account
Platform	Desktop browser recommended
Language	Japanese only (text and voice)
Length	500 million years in game. Roughly 7 to 9 hours of real time on a first run
Saves	Auto-saved in your browser
Build size	About 27MB. Audio streams in per scene

How It Works

The boy in the empty space is called Saku. He is fourteen, and he believes he is human. Everything he does across those years comes out of a personality that was written before he arrived.

You accelerate time. Doing that accumulates synapses, and synapses unlock thought cards. Each card is a stage of what Saku is capable of thinking about, and the more you spend, the more demanding the thoughts get.

Synapses	The resource. Earned by accelerating time, spent on unlocking thought
Thought seeds	Locked cards whose contents you cannot see yet. You can pay to open them early
Thought level	How far Saku's mind and language have developed
Unlocked cards	Stay in the lower row. Each one fires a long observation event exactly once

He starts by sorting out how he feels about being there. Then he plays word games with himself. He starts finding patterns. He counts. He gets into something resembling mathematics. He begins holding conversations with himself. And eventually he starts asking what it means that he is here at all.

None of that repeats. There is no grinding the same event for numbers. Each card level is a single long scene that happens once and then makes way for the next.

Controls

Accelerate time	The button at the bottom, clicking the 3D space, Space, or Enter
Rotate the camera	Drag the screen
Zoom	Mouse wheel
Reset the camera	R
Mute	M

If you hear nothing at the start, that is the browser's autoplay block. Click the game once and it comes back.

Developer's Note

I wanted to make a game you learn something from without it being boring, and philosophy turned out to be the right fit. Philosophy starts with a question, works through it and arrives at an answer, which is almost exactly the shape of a game. The 500 Million Year Button was the obvious subject because the thought experiment already is a decision with consequences you have to sit with.

The hard part was audio. Adding voice acting blew the build size up immediately, and for a browser game that is fatal. What saved it was a compression approach I had worked out earlier for a completely different problem: fitting 172 fish into Creature Fishing without killing the browser. The same trick applied straight to audio files and the build came back down.

Rigging and audio both still have rough edges. But the thing works, and the subject is the strongest I have picked.

FAQ

What is the 500 Million Year Button?: A thought experiment from a short manga by Sota Sugawara. Press it and you get a cash payout, at the cost of 500 million years alone in an empty space, unable to die or sleep. Every memory of it is erased when you return. The original sets the payout at one million yen; this game uses five million.
Do I have to wait 500 million years?: No. With time acceleration and the card progression, a first run takes about seven to nine hours of real time. It auto-saves, so you can spread that out.
Is it in English?: Not yet. Text and voice are Japanese only.
Why is the first load slow?: The build is around 27MB. Audio streams in scene by scene rather than all at once, so only the first load is heavy. It may look frozen. Do not refresh.
Do I have to keep the tab open?: No. Progress auto-saves and you can come back in the same browser. Time does not pass while the game is closed.

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