I'm a fool. If I'd bothered to look it up first, I would have remembered that the actor model was integral to the invention of Scheme. See Sussman & Steele, Sch

I'm a fool. If I'd bothered to look it up first, I would have remembered that the actor model was integral to the invention of Scheme. See Sussman & Steele, Scheme: An Interpreter for Extended Lambda Calculus (AI Memo 349), 1975 (the first link at http://library.readscheme.org/page1.html http://library.readscheme.org/page1.html). From the acknowledgements: This work developed out of an initial attempt to understand the actorness of actors. Steele thought he understood it, but couldn't explain it; Sussman suggested the experimental approach of actually building an "ACTORS interpreter". This interpreter attempted to intermix the use of actors and LISP lambda expressions in a clean manner. When it was completed we discovered that the "actors" and the lambda expressions were identical in implementation.