Early Bitcoin pioneer Hal Finney shared his vision for zero-knowledge proofs 25 years ago, a full decade before the launch of the first cryptocurrency, Bitcoin.
Purportedly from the Crypto ’98 conference in Santa Barbara on August 26, 1998, Finney discussed in detail the concept of zero-knowledge proofs, a cryptographic technique that would gain widespread popularity decades later.
Finney explains how hypothetically a zero-knowledge proof is performed on a SHA-1 hash, describing the possibility of sending a cryptographic statement without revealing any details contained in the same statement.
“I want to prove to you that I know a message that hashes to a given hash using the SHA-1 hash. I don’t want to reveal anything about the message to you. This is a zero-knowledge proof that I There’s a program written to do that, I’ll tell you about it,” Finney explained.
A zero-knowledge (ZK) proof is a cryptographic protocol that enables one user (the prover) to convince another user (the verifier) that a specific statement is true without revealing any details about the statement itself.
At the time of Finney’s lecture, zero-knowledge proofs were considered a possibility, but were widely considered to be, as Finney put it, “inefficient or impractical” due to the hardware limitations of the time.
