American comedian and actor George Gobel (1919-1991) hosted Light’s Diamond Jubilee, a two-hour TV special that aired on October 24, 1954 on all four U.S. television networks of the time (DuMont, CBS, NBC and ABC). Gobel joked:
 
“Just think, if the string on Benjamin Franklin’s kite had broken, tonight we’d all be watching TV by candlelight!”
 
The line immediately became popular, but American inventor Thomas Edison (1847-1931) soon replaced Benjamin Franklin. “If it hadn’t been for Thomas A. Edison, we would be watching television by candle light” was cited in 1957. “And did you ever stop to think that if it weren’t for Tom Edison we’d be watching TV by candlelight?” was cited in 1959.
 
   
Wikipedia: Thomas Edison
Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and the long-lasting, practical electric light bulb. Dubbed “The Wizard of Menlo Park”, he was one of the first inventors to apply the principles of mass production and large-scale teamwork to the process of invention, and because of that, he is often credited with the creation of the first industrial research laboratory.
 
Wikipedia: George Gobel
George Leslie Gobel (May 20, 1919 – February 24, 1991) was an American comedian and actor. He was best known as the star of his own weekly NBC television show, The George Gobel Show, which ran from 1954 to 1960 (the last season on CBS, alternating with The Jack Benny Program).
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On October 24, 1954, Gobel hosted Light’s Diamond Jubilee, a two-hour TV special broadcast on all four US television networks of the time.
 
25 October 1954, Cedar Rapids (IA) Gazette, pg. 10:
“Just think.” said Gobel, “if the string on Benjamin Franklin’s kite had broken, tonight we’d all be watching TV by candlelight!”
     
26 October 1954, San Diego (CA) Union, “‘Light Jubilee’ Rated Superb TV” by Donald Freeman, pg. B-3, col. 2: 
“If Ben Franklin’s kite had broken down,” said Gobel, “we’d all be watching TV by candlelight.”
 
Which may not make much sense but at least it’s illogical.
 
Google Books
Current Biography Yearbook
New York, NY: H. W. Wilson Co.
1956      
Pg. 233:
According to Cue (November 6, 1954), the television star’s one-line comment on the Diamond Jubilee of Light program in praise of Edison, “If it weren’t for electricity, we’d all be watching television by candlelight,” will become “one of the ...
 
Google Books
Official Proceedings of the New York Railroad Club
Volume 68
1957
Pg. 135:
As one wag has said, if it hadn’t been for Thomas A. Edison, we would be watching television by candle light (Laughter).
 
5 September 1959, Boston (MA) Daily Record, “‘Crazy-Legs’ Joins TV Ranks” by John Gillooly, pg. 22, col. 1:
And did you ever stop to think that if it weren’t for Tom Edison we’d be watching TV by candlelight?
 
Google Books
Celebrity Register:
An Irreverent Compendium of American Quotable Notables
By Cleveland Amory
New York, NY: Harper & Row
1960
Pg. 293:
One of his (George Gobel—ed.) typical lines was his reaction to the Diamond Jubilee of Light TV program honoring Thomas Edison: “If it weren’t for electricity, we’d all be watching TV by candlelight.”
 
23 February 1963, Hartford (CT) Courant, “Today’s Chuckle,” pg. 1, col. 3:
If it weren’t for Thomas A. Edison, we’d be watching TV by candlelight.
 
Google News Archive
21 January 1968, Reading (PA) Eagle, “My Favorite Jokes” by Ukie Sherin, Parade magazine, pg. 23, col. 1:
Do you realize that if it wasn’t for Edison…we’d be watching television by candlelight!
 
Google Books
The 2,548 Wittiest Things Anybody Ever Said
By Robert Byrne
New York, NY: Touchstone
2012
1,487
If it weren’t for electricity, we’d all be watching television by candlelight. —George Gobel (1919–1991)
 
Google Books
The Official Rules:
5,427 Laws, Principles, and Axioms to Help You Cope with Crises, Deadlines, Bad Luck, Rude Behavior, Red Tape, and Attacks by Inanimate Objects
By Paul Dickson
Mineola, NY: Dover Publications, Inc.
2013
Pg. 35:
Boliska’s Realization: Do you realize that if it weren’t for Edison, we’d be watching TV by candlelight? (Ed Boliska, quoted in Jack Smith’s column, Los Angeles Times, February 11, 1981; RS.)
 
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Milton Berle: We owe a lot to Thomas Edison. If it wasn’t for him, we’d be watching TV by candlelight. | #Quotes
10:23 AM - 8 Mar 2016