Interestingly both had a relationship to a NLS in there lives.
For Andrew, it was Non-Linear Systems, where Andrew invented the digital voltmeter.
For Alan, it was oN-Line System, where he attended "The Mother of All Demos", which spawned the mouse and some other inventions used in the Xerox Alto, which is where Smalltalk was primarily developed initially.
https://en.wikipedia.org/wiki/Sketchpad
https://engineeringcommunity.net/2025/05/02/ivan-sutherland/
Alan Kay Did Not Invent Objects - https://news.ycombinator.com/item?id=19985776 - May 2019 (13 comments)
> Finally, another graduate student and I unrolled the program listing 80 feet down the hall and crawled over it yelling discoveries to each other. The weirdest part was the storage allocator, which did not obey a stack discipline as was usual for Algol. A few days later, that provided the clue. What Simula was allocating were structures very much like the instances of Sketchpad. There were descriptions that acted like masters and they could create instances, each of which was an independent entity. What Sketchpad called masters and instances, Simula called activities and processes. Moreover, Simula was a procedural language for controlling Sketchpad-like objects, thus having considerably more flexibility than constraints (though at some cost in elegance) [Nygaard, 1966, Nygaard, 1983].
taylodl•3d ago
Rochus•3d ago
Not actually. Kay's view of OO is pretty different from what we understand of OO today; the general understanding is closer to Simula 67; see also the IEEE milestone: https://ethw.org/Milestones:Object-Oriented_Programming,_196.... Ironically Smalltalk-76 and onwards also corresponds more with the Simula 67's than Kay's view.
> Development of Smalltalk started in 1969
You mix that up with Kay's PhD. A good and reliable history about the origin and evolution of Smalltalk can be found in the excellent 2020 paper by Ingalls: https://dl.acm.org/doi/10.1145/3386335
chao-•4h ago
Indeed, in his own words, from 1998:
https://wiki.c2.com/?AlanKayOnMessaging
He also gave at least two conference talks where he explained how his view of objects sending messages was in line with his background in molecular biology: he thought of the objects like cells sending messages via exchanging various chemicals. I don't have either on hand, but I believe one time he shared this was in an interview with Joe Armstrong.
Rochus•4h ago
I don't think he has a formal education in molecular biology (didn't find any (independent) evidence), and I don't think the analogy he draws between his view of messaging and biochemical signaling really works. His messages are directed to specific objects, whereas in a biological system, enzymes and the like are dumped into the bloodstream indiscriminately without a specific target. Biological systems, in constrast to software systems, lack centralized orchestration, relying on emergent behavior from local interactions instead.
Jtsummers•4h ago
At least the ACM believes he does.
https://amturing.acm.org/award_winners/kay_3972189.cfm
Rochus•3h ago
cxr•2h ago
<https://www.chilton-computing.org.uk/inf/pdfs/kay.htm>
Rochus•2h ago
0x445442•3h ago
Rochus•2h ago
andrekandre•49m ago
[0] https://www.youtube.com/watch?v=QjJaFG63Hlo
(he starts talking about that around 12 mins)
AceJohnny2•4h ago
https://lists.squeakfoundation.org/pipermail/squeak-dev/1998...
(edit: derp, this is directly cited in TFA)
Also, I loved this interview/discussion between Kay & Joe Armstrong, inventor of Erlang, where the topic comes up again (because Erlang is also a lot about messaging between agents)
https://www.youtube.com/watch?v=fhOHn9TClXY
chao-•4h ago
AceJohnny2•4h ago
layer8•4h ago
Rochus•4h ago
twoodfin•3h ago
Rochus•3h ago