Yeah but apart from SBCL, Viaweb, Hacker News, Emacs, Clojure, Scheme, Racket, garbage collection, macros, homoiconicity, the REPL, S-expressions, symbolic computation, what has Lisp ever done for us?

...booleans, conditional expressions, first-class functions, lambdas, closures, eval...

Booleans? I think some guy named Boole might have prior art...

(Yeah, OK, he didn't have a programming language...)

booleans as values of course.

arguably redundant since GP did say symbolic communication, but Lisp had T before Algol 60 came out