The year after "The History of Scheme", Steel gave a slightly modified talk called "Designing by Accident", available at www.slideshare.net/timmenzies/… .

Slideshare is an Absolutely Proprietary site, but with LibreJS or JS simply turned off you can readily see the text of all the slides neatly listed.

Slide 45 (Slide 44 in "The History of Scheme"):

> An Astonishing Conclusion

> Actor constructors and lambda expressions in our toy language are operationally equivalent.
> Does it follow that actors are “merely” functions in a tail-recursive, lexically scoped language?
> They are the same mechanism. Any difference is not inherent, but depends only on what you put in their bodies.
> If your primitive operators are functions, you will tend to write programs in a functional style.
> If your primitive operators are actors, you will tend to write programs in an actor style.

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