“Old math teachers never die—they just become irrational”

“Old soldiers never die—they just fade away” is an old saying that was popularized by General Douglas MacArthur (1880-1964) in his farewell address to Congress on April 19, 1951. Many parodies of the saying have been made.
 
There have been many math versions. “Old math teachers never die, they just become irrational” was posted on Twitter on April 13. 2009.
 
“Old math teachers never die—they just reduce to lowest terms” and “Old mathematicians never die—they just lose some of their functions” are related sayings.
 
     
Twitter
Robert Popoff‏
@Rob_Popoff
Old math teachers never die, they just become irrational.
11:29 PM - 13 Apr 2009
     
Twitter
PuterPrsn™‏
@PuterPrsn
Old math teachers never die, they just become irrational. #pun
8:50 PM - 17 Apr 2009
 
Twitter
Murray Bourne‏
@intmath
Daily Math Tweet: Old math teachers never die, they just become irrational. #math
8:00 AM - 10 Jun 2009
 
Google Groups: Bayanihan Books Project
A case of media outlets fudging a revealing statement of a favored presidential bet
Jose Carillo
4/30/10
(...)
The Finest in Language Humor: Puns About Education (Sampler – “Old math teachers never die, they just become irrational.”)
     
wattpad
Math Puns
by _spaced_out
April 23. 2016
(...)
Old math teachers never die, they just become irrational.
     
Twitter
eatjobs‏
@eatjobs
Old math teachers never die, they just become irrational. #UKPunDay
#teacher #teacherlife #teachingvacancyuk #education #punday
9:49 AM - 12 Feb 2018