this post was submitted on 30 Jan 2026
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xkcd

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xkcd #3201: Proof Without Content

Title text:

There's also a proof without content of a conjecture without content, but it's left as an exercise for the reader.

Transcript:

Transcript will show once it’s been added to explainxkcd.com

Source: https://xkcd.com/3201/

explainxkcd for #3201

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There really is an XKCD for everything.

[–] palordrolap@fedia.io 5 points 2 months ago

That blank box is a proof if and only if it is a proof. That makes it a self-reference and has no truth value.

[–] this@sh.itjust.works 5 points 2 months ago

A white square still counts as content.

[–] panda_abyss@lemmy.ca 2 points 2 months ago (1 children)

I suppose a boltsman brain could come into existence with a proof of the Poincare conjecture in it's mind, then poof out of existence.

[–] wolframhydroxide@sh.itjust.works 2 points 2 months ago (1 children)

Isn't the idea of a Boltzmann Brain not that it poofs out of existence, but that there is no way to prove that you are not a Boltzmann Brain, and all of your perceived experiences could be confabulation? In such a scenario the Brain needn't poof out of existence; merely continuing to exist for but a moment would belie the true nature of their consciousness, as the brain quickly suffocates and dies, losing its contents.

[–] panda_abyss@lemmy.ca 1 points 2 months ago

I’ve heard it both ways. 

It’s far more likely you aren’t a boltsman brain and that one has never existed. 

[–] SpikesOtherDog@ani.social 1 points 2 months ago

The proof cannot exist without the conjecture.

[–] Hamartiogonic@sopuli.xyz 1 points 2 months ago* (last edited 2 months ago)

It's the trivial proof.

[–] GraniteM@lemmy.world 1 points 2 months ago

But that's not a convincing proof.

[–] NachBarcelona@piefed.social 1 points 2 months ago

But that's both words and content. It's contradictory.