@ecadre @glyph Well, the citations at https://en.wikipedia.org/wiki/Emacs suggest a 1976 date as the first development of Emacs.
The citations at https://en.wikipedia.org/wiki/Linux suggest Linus Torvalds enrolled in a Unix course in 1990 and during that course began to conceptualize the Linux kernel, which he released in 1991.
If those dates are incorrect or I'm missing something about 1991 being "at least" 10 years after 1976, please let me know. Please also update the articles above with more citations as well as https://en.wikipedia.org/wiki/Time and https://en.wikipedia.org/wiki/Mathematics if appropriate to helping me understand those concepts better when writing absurdist replies to someone's facepalm post.