Explanation behind why Satoshi picked a “useless” task for PoW algorithm

Satoshi had to pick some “work” which was essentially useless. Had he picked something useful such as graphics processing, then companies which used that work would have a leg up over others.

The key point is about dual-use advantages – preventing companies from benefiting when the mining work itself has value outside of mining.

• Bitcoin (useless hashing): No one benefits from the computation output itself. Mining companies compete on electricity/hardware, but the work product has no external value

• Hypothetical “useful work” mining (like graphics rendering, protein folding, AI training): Companies already doing that work for their business would get mining rewards on top of their existing value creation. They’d be getting paid twice – once for the useful output, once for the mining reward.

Eg. If mining work overlapped with AI training work, AI companies would dominate mining because they’re already doing similar computation for business purposes.

By picking something useless, he ensured that Bitcoin miners were speaking truth. They wouldn’t do all this work to lie.