From ZmnSCPxj at protonmail.com  Thu Dec 16 14:12:43 2021
From: ZmnSCPxj at protonmail.com (ZmnSCPxj)
Date: Thu, 16 Dec 2021 14:12:43 +0000
Subject: [Lightning-dev] A blame ascribing protocol towards ensuring
	time limitation of stuck HTLCs in flight.
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Good morning Bastien,



> * it's impossible for a node to prove that it did *not* receive a message: you can prove knowledge,
> ? but proving lack of knowledge is much harder (impossible?)

Yes, it is impossible.

If there could exist a proof-of-lack-of-knowledge, then even if I personally knew some fact, I could simply run a virtual machine that knows everything I know *except* for that piece of knowledge, and generate the proof-of-lack-of-knowledge there.
This leads to a contradiction, as I myself *actually* know the fact, but I can present the proof-of-lack-of-knowledge by pretending to be somebody ignorant.

Regards,
ZmnSCPxj (I definitely do not know that I am an AI)