Recently, while reviewing the early history of Bitcoin, I rediscovered the name Hal Finney. The more I think about it, the more I believe that the story of this cryptography pioneer deserves to be known by more people.

Hal Finney was not just an observer; he was a true builder. In the development of the PGP encryption system, he worked alongside Phil Zimmermann to lay the foundation for global email encryption. Even more impressively, he created the first cryptography-based anonymous email relay, a concept that later directly inspired the birth of privacy tools like Tor.

That 2004 step was even more critical. Hal Finney proposed "Reusable Proof of Work" (RPOW), which used a trusted computing environment to enable token reuse, solving the one-time issue of traditional PoW. The industry widely considers this to be the inspiration for Bitcoin’s PoW mechanism.

When Satoshi Nakamoto released the Bitcoin white paper in 2008, support within the cryptography community was limited, but Hal Finney immediately downloaded the code and began testing. He became the first person outside of Satoshi to run a Bitcoin node, mining about 70 early blocks. The most famous was the transaction on January 12, 2009—Satoshi sent him 10 BTC, marking Bitcoin’s first real peer-to-peer transaction, turning decentralized currency from theory into practice.

Finney was not just mining; he also helped Satoshi fix client vulnerabilities, optimize transaction speed, and develop tools to enhance wallet security. These were detailed tasks, but it was these details that allowed Bitcoin to truly operate.

His vision was also remarkably forward-looking. In 2010, he predicted that Bitcoin would become a reserve currency for banks, analogous to gold’s role in traditional finance. He also said a classic phrase: "Bitcoin must be expensive to ensure security," emphasizing the relationship between coin value and computational power security. In an email from 2009, he even estimated that if Bitcoin captured global wealth, a single coin could be worth 10 million dollars.

But Hal Finney’s story is also heavy. In 2009, he was diagnosed with ALS (amyotrophic lateral sclerosis), gradually becoming paralyzed and eventually only able to program with eye-tracking devices. Most people might have given up long ago, but he continued developing Arduino-powered wheelchair controls and optimizing Bitcoin wallet security. These are small details, but it is these details that made Bitcoin truly functional.

His vision was also extraordinarily ahead of its time. In his early years, he signed up for cryonics. After passing away in 2014, his body was preserved at -196°C by the Alcor Foundation in Arizona, waiting for future technology to possibly revive him. His wife, Fran, recalled what he said: "He never promised ‘I will come back,’ only ‘I hope to come back.’"

Some suspect he was the true creator of Bitcoin because of his close communication with Satoshi and their shared city residence. But analysis of his correspondence and the timeline of his illness actually weaken this hypothesis—by the time Satoshi was active, Hal Finney was already losing his ability to type.

In his final words, he wrote: "Even with ALS, my life remains fulfilled... Bitcoin is the legacy I leave for the future." Today, his cold wallet still holds early mined Bitcoin, quietly waiting. Hal Finney embodies the purest ideals of early Bitcoin—technological empowerment, decentralization, and individual sovereignty. These ideals continue to inspire a new generation of builders today.