One of the early cryptocurrency pioneers and one of the candidate to be Satoshi Nakamoto.
Szabo is a cryptographer, computer scientist and lawyer. He started dealing with many of the ideas we discuss regularly in the blockchain and cryptocurrency world long before the introduction of Bitcoin.
During late 1990s, he developed Bit Gold. It was a decentralized digital currency that was never implemented but is believed to be a precursor to Bitcoin.
Smart Contracts
This is a concept that is fairly well known in the cryptocurrency world. Ethereum rose to prominence since it immediately incorporated smart contract technology into its platform. It was not something the Ethereum developers came up with.
It is an idea that reverts back to Szabo. He came up with the idea in the 1990s, believing this was a way to revolutionize the legal profession. The vision was a digital marketplace built on these automatic, cryptographically secure processes. Hence, it formed a place where transactions and business functions can happen without intermediaries. Trust was established by the code.
We can see where code is law comes from.
Double Spend Problem
One of Szabo's greatest "failures" was his inability to solve the double spend problem. This is what doomed Bit Gold. While he was able to get his system operating, it required a centralized entity to eliminate this. Of course, this was viewed as the end of the road for the early innovators.
It was also something that Satoshi solved with Bitcoin. This might actually be blockchain's greatest contribution.
The Nakamoto Controversy
Due to his work with Bit Gold, many feel that Szabo is Satoshi Nakamoto. Elon Musk, for one, seems convinced this is the case. It was looking into based upon his writings along with other indications of his tied to Satoshi.
The Aston University Centre for Forensic Linguistics conducted a linguistic study on Bitcoin’s white paper to determine the identity of Nakamoto. The group concluded that Nick Szabo was Nakamoto based on linguistic similarities.
Many feel that anonymity of the founder is vital due to decentralization.
Cypherpunks
Szabo was one the original cypherpunks dating back to the 1980s. The idea of decentralization and privacy were some of the core tenets this group. They were the ones who fought the US Government over the battle of encryption when that was being looked into for banning.
In addition to Szabo, David Chaum also played around with the idea of decentralized digital money with ECash. Both are considered predecessors to Bitcoin.