“If/When the solution is simple, God is answering/speaking” is a quotation that has been credited to Albert Einstein (1879-1955), a physicist who was known for finding simple solutions to complex physics problems. There is no evidence that Einstein ever said it. “If the solution is simple, God is answering” has been cited in print since either 1988 in Esquire magazine (the citation has not been verified) or ““When the solution is simple, God is answering” in 1995. Neither known citation is close to the time span when Einstein lived.
 
The Einstein-credited quotation became very popular in the 2000s and was cited in many science, business and religion texts.
 
   
Wikipedia: Albert Einstein
Albert Einstein 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who developed the general theory of relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and the most influential physicist of the 20th century. While best known for his mass–energy equivalence formula E = mc2 (which has been dubbed “the world’s most famous equation”), he received the 1921 Nobel Prize in Physics “for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect”. The latter was pivotal in establishing quantum theory within physics.
   
Wikiquote: Talk:Albert Einstein
Unsourced and dubious/overly modern sources
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If the solution is simple, God is answering.
. Didn’t find any published sources earlier than Esquire: Volume 106 (1988). Hypnosifl 00:03, 6 December 2011 (UTC)
 
A Selection of Quotes from Albert Einstein
From a UseNetPost by .(JavaScript must be enabled to view this email address) (Colin Douthwaite), 27 Mar 1995 05:06:19 GMT
A collection of One Liners ....
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“When the solution is simple, God is answering.”
 
Google Books
Bite-Size Einstein:
Quotations on Just About Everything from the Greatest Mind of the Twentieth Century
Compiled by Jerry Mayer & John P. Holms
New York, NY: St. Martin’s Press
1996
Pg. 61:
When the solution is simple, God is answering.
 
Google Books
Fractal Imaging
By Ning Lu
San Diego, CA: Academic Press
1997
Pg. 1:
When the solution is simple, God is answering.
— What I believe
Albert Einstein
 
Google Books
How to Think Like Einstein:
Simple Ways to Break the Rules and Discover Your Hidden Genius
By Scott Thorpe
Naperville, IL: Sourcebooks, Inc.
2000
Pg. 21:
“When the solution is simple, God is answering.”
—ALBERT EINSTEIN
 
Google Books
My Einstein:
Essays by Twenty-four of the World’s Leading Thinkers on the Man, His Work, and His Legacy
Edited by John Brockman
New York, NY: Pantheon Books
2006
Pg. ?:
The role of Der Alte is summed up in another pair of quotes. “When the solution is simple, God is answering.” And this comment, after Arthur Eddington’s eclipse expedition, confirmed the (corrected) prediction of general relativity, to the effect that Einstein would feel sorry for God if the confirmation had not been made, because “the theory is correct.”
 
Google Books
The Simplest Book God Ever Wrote
By Sunirmalya Symons
Deepwater, Qld. Australia: Heart Garden Publishing
2007
Pg. 72:
Einstein famously said that when ‘the solution is simple, God is speaking’. He used this principal extensively in crossing many new boundaries in science, including perhaps his most famous ‘E=mc2’.
     
Great Thoughts
Friday, March 11, 2011
Albert Einstein Quotes on Philosophy of Religion, Theology, God
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When the answer is simple, God is speaking. (Albert Einstein)
   
A.V. Club
West Wing cast reunites to make you feel safe (and vote)
By Sarah Collins September 20, 2012
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As the presidential campaign crawls to its spiteful peak, Martin Sheen’s sonorous Einstein quote just makes politics seem so inviting again.
(Martin Sheen says, “When the solution is simple, God is answering,” 3:30 minutes into the video—ed.)