In 2011 Carl Hewitt organized a workshop on "Inconsistency Robustness"; I took this as an excuse to indulge my penchant for half-baked philosophical flaming and wrote a paper based on my dissatisfactions with the state of knowledge representation in science. The paper and my slides are available.
In traditional software—both then and now—such modules are subroutines, functioning together like the parts of a car engine function together: the ensemble of subroutines is flowcharted, engineered to work together in completely well understood interactions to solve a particular class of problem. Their “range of independent thought” is as null as, say, a carburetor’s.
In the early 1970s, Alan stretched that paradigm and warped it into a new one, imagining the subroutines not like the parts of a mechanical device but more like a set of humans tasked with solving a problem, where one might relax the degree to which their actions and interactions are prescribed. As with human beings, Alan reasoned, it might be worth educating the modules— investing resources in making each module smarter and more flexible—and then relying on the resultant community of agents to solve problems in ways not fully preconceived by their developers. In other words: make them smarter, better informed, give them higher level responsibilities, and then give them more freedom to meet their goals.
This zeitgeist thundered through Carl Hewitt’s ACTORS , Seymour Papert ’s LOGO , my own BEINGS , and of course Alan Kay and Adele Goldberg’s Smalltalk , and has reverberated ever since, sometimes explicitly as in the case of Mixins (in Lisp Machines FLAVORS  and, more recently, in Java) and sometimes almost unrecognized as in the case of Expert Systems  and, more recently, the Semantic Web.
MIT Computer Scientist, best known for development of the Actor model of computation, which was hugely influential and still continues to be. A very idiosyncratic thinker, with a nose for important big ideas. Died at the end of 2022: Carl Hewitt Obituary (1944 - 2022) - Aptos, CA - Santa Cruz Sentinel. It's a bit hard to appreciate today, when every toaster is connected to the internet, how visionary and forward-thinking his thinking about distributed computing was in its day. Basically he foresaw this world and tried to develop intellectual tools for building and controlling it.
Like many of the early CS pioneers his vision has yet to see full fruition. There are many languages and systems that incorporate something called actors, but that is different from an actual actor-based system, something that has that kind of radical distributedness build into the foundations. Here's one recent effort that seems in the right spirit: Growing a Networked Garden with Spritely Goblins -- Spritely Institute
Carl had a reputation for being difficult to understand; his MIT colleagues in the 70s apparently just could not get the idea of Actors (that seems strange to me, but I'm of a different generation where maybe that stuff was more part of the common culture, by way of object-oriented programming). I myself had a lot of trouble understanding his later theories about inconsistency robustness, which may also just be way ahead of their time. For someone who spent a lifetime failing to be understood, he had remarkable patience and was always ready to explain his ideas to whoever would listen.
This was a significant early AI system that introduced not one but two very important notions: backtracking and pattern-directed invocation. It was the ancestor node of a bunch of other AI work from the 70s and 80s including Terry Winograd's SHRDLU.
Actors and Distributed Systems
Actors is a formalism for describing concurrency, but there were rather less formalized versions of the underlying ideas, such as The Scientific Community Metaphor. It also is quite obviously related to Society of Mind. Minsky was Hewitt's advisor.
Actors and Scheme have a complicated shared history; the tl;dr version is that Scheme was developed out of an effort to try to understand and implement Actor ideas, although I think Carl disputed this.
My own presentation at the 2011 workshop was on Politics and Pragmatism in Scientific Ontology Construction, where I was lightly mocking the idea of consistent formal ontology. I also participated in a panel organized by Fanya Montalvo on the Singularity, and did a short presentation on How to Avoid the Singularity, apparently I was taking pokes at rationalists even back then. This talk was trying to connect Hewitt's ideas with Latour, in a jokey way.
It's kind of funny that Latour's Actor-Network Theory is about as prominent in his intellectual world ans Hewitt's Actors is in computation, yet the two don't seem to be very connected (Both died during 2022). Hewitt was aware of Latour at least, I asked him once about his thoughts on ANT and he said "we're implementing it!"