Fen Labalme did confirm Stallman's claim, but could not find the email; remember this is in the days of backups on 9-track tapes, and he was looking for an email he had presumably deleted several years earlier.
> It's important here to note that Stallman does not claim it was his own brainchild, and did give Gosling credit.
This is true in a very limited way, but by itself it is a very misleading partial truth. Stallman gave Gosling credit for Gosmacs, not for EMACS.
Stallman had been working on EMACS on ITS on the PDP-10 for years before Gosling started writing his version, but the inception of EMACS was, as I understand it, a collaboration between Stallman, Steele, and Moon — a set of macros for ITS TECO, which was maintained by Stallman https://github.com/PDP-10/its/issues/1633. Gosling's Emacs wasn't even the second Emacs; Multics Emacs was Bernie Greenberg's reimplementation of the PDP-10 EMACS Stallman was the maintainer of, and it was the first (corrected by trn: second) Emacs to use Lisp as its scripting language, which is where Gosling got the idea. EINE (the first version of Lisp-Machine Emacs, as trn corrected me below) and ZWEI also preceded Gosmacs.
From the Emacs FAQ https://www.gnu.org/software/emacs/manual/html_node/efaq/Ori...:
> Emacs originally was an acronym for Editor MACroS. RMS says he “picked the name Emacs because E was not in use as an abbreviation on ITS at the time.” The first Emacs was a set of macros written in 1976 at MIT by RMS for the editor TECO (Text Editor and COrrector, originally Tape Editor and COrrector) under ITS (the Incompatible Timesharing System) on a PDP-10. RMS had already extended TECO with a “real-time” full-screen mode with reprogrammable keys. Emacs was started by Guy Steele as a project to unify the many divergent TECO command sets and key bindings at MIT, and completed by RMS.
Gosling wrote Gosmacs in 1981, five years later, as a copy of Stallman's work; Stallman published a widely-cited paper that year describing many features of EMACS which were unusual or unique at the time, but are now the standard way to design text editors: https://dspace.mit.edu/bitstream/handle/1721.1/5736/AIM-519A.... Gosling sold his Unix clone of Stallman's Emacs to UniPress in 1983, after Stallman had spent seven years writing the editor Gosling had copied; Stallman's version had perhaps a thousand users before Gosling wrote a line of Gosmacs.
Stallman tells the story in 2002 in the lecture linked above. Other people like Bernie Greenberg confirm Stallman's version.
I find it quite dispiriting that 34 years after The Great Emacs Copyright Debate was conclusively settled (by Stallman replacing the disputed redisplay code with a better algorithm, three months after the initial release of the first version of GNU Emacs and the ensuing hue and cry) we are still having to rebut Gosling's baseless slander of the man whose work Gosling copied to get rich.