@screwtape Here is the specific email, and idea to the name (my original date is wrong, but whatever). Since the file was called ?MACS .. it also got renamed to EMACS.
RMS@MIT-AI 11/10/76 21:46:03
To: EAK at MIT-AI, CBF at MIT-AI, GLS at MIT-AI, ED at MIT-AI
To: DLW at MIT-AI, MOON at MIT-AI
Unless anyone can think of a better idea, I think we should
rename ? to E.