I totally understand not wanting to be an unwitting mule transporting illegal numbers like bits representing CP when processed correctly.

Mechanic notes that running a node makes you a sender and receiver of illegal numbers (such as binary digits representing CP) because nodes are in the business of sending and receiving blocks and consensus rules do not prevent certain sequences of bits from being embedded via op return (which had been done since forever) or inside cleverly constructed public keys (recent development).

So Mechanic wisely restricts his consideration to each nodes mempool, somehow believing that illegal numbers in RAM are somehow going to be treated differently than illegal numbers on disk (one can persist mempool to disk though and can chose not to evict any transaction ever if they wish). I don’t think the law will see it that way, but from a moral perspective I totally agree with Mechanic. I’m not sure a court will care whether you have to type or copy/paste a command or double click a file to reveal illegal numbers.

Here’s an interesting example: if you run a node, copy and paste this in to the terminal:

bitcoin-cli getblock 00000000000000ecbbff6bafb7efa2f7df05b227d5c73dca8f2635af32a2e949 0 | tail -c+92167 | for ((o=0;o<946;++o)) ; do read -rN420 x ; echo -n ${x::130}${x:132:130}${x:264:130} ; done | xxd -r -p | tail -c+9 | head -c184292 > bitcoin.pdf

Now you have your own copy of a 184 kB computer file that happens to be a PDF file with embedded images. But a similar command could reveal something vile and illegal.

Now I agree that the miner who mined the block containing illegal numbers should never knowingly do so. And forcing illegal numbers to be submitted directly to a miner does provide a chain of responsibility and a legal target for law enforcement, much like OFAC address ban list already does.

But as soon as miners figure out how to detect illegal numbers to rightly filter them, the bad people sending illegal numbers will just become more clever at obscuring the data. One must accept that bitcoin can and will be used to publish the most disgusting and evil of all illegal numbers eventually, if costs of doing so remain sufficiently low.

If one wanted to be as “blameless” as possible while running a node, perhaps the best way is to either run a satellite node that transmits nothing or run a conventional node in “blocks only” mode that forgoes the mempool entirely.

But this old issue of illegal numbers is something bitcoin has been dealing with for years. And if bitcoin can’t be censorship resistant enough to be unaffected by the worst of illegal numbers, it can’t be censorship resistant enough to serve as money. Just like proof of work “wastes” energy, bitcoin will transport illegal numbers if bad people make it do so.