It’s been six years since Hal Finney passed away from the Amyotrophic Lateral Sclerosis, or ALS. Finney is known as an early supporter of Bitcoin (BTC), and one of the first people to respond to Satoshi Nakamoto’s initial post on the cypherpunk mailing list. In Bitcoin’s earliest days, he was the only one who fully understood the possibilities of the technology, without being overtly skeptical about its prospects.
Finney was one of the better-known cryptographers in the cypherpunk community even prior to his involvement with Bitcoin. Early in his career, he worked for the PGP Corporation, which owned Pretty Good Privacy computer software, and allowed users to encrypt their texts, emails, and files. In 2004, Finney developed Reusable Proof-of-Work software, or RPOW. Unlike Adam Back’s Hashcash and much like Bitcoin, the proof-of-work was indeed reusable, hence the name. This invention was one of the major stepping stones on the path towards Bitcoin, though Satoshi did not cite Finney’s work in his white paper.
Cryptographer Adam Back told Cointelegraph that he had had some email exchanges with Finney over the years, including a request for Back to comment on RPOW. Though they never met in person, Back remembers Finney fondly:
Well, I never met him in person, but I consider him to be a constructive personality more interested in building things than arguing about politics. While building things with cypherpunk intent, he would just focus on the constructive part of conversations. Don’t think I ever saw him participate in online arguments on the cypherpunks list.
Hal Finney was the first person outside of Satoshi to start mining Bitcoin, and was also the recipient of the first Bitcoin transaction. While the progression of his disease was initially slow, he spent the last months of his life completely paralyzed. In his farewell post on Bitcointalk.org, he downplayed his involvement in Bitcoin. Even so, he is remembered fondly as one of Blockchain’s greatest contributors.
Prior to his death, Finney and his wife Fran worked to raise awareness and fundraising for ALS. Since his departure, Fran Finney has continued her husband’s legacy.