Paul Graham
Programmer and essayist, author of ANSI Common Lisp, which lisp-lang.org lists in its books section. He appears in this wiki as the authority common-lisp‘s community site leans on for its central claim: a language that can absorb new abstractions does not go out of style.
Worth noting what that makes him here. He is not a steward of the language in the sense language-governance uses — he holds no committee seat, funds no core team, ships no implementation. The site cites him the way a marketing page cites a customer, and his argument is the only thing on that page doing the work a design rationale usually does.