“There are some ideas so wrong that only a very intelligent person could believe in them”

“There are some ideas so wrong that only a very intelligent person could believe in them” has been credited to George Orwell (the pen name of Eric Arthur Blair, 1903-1950) since at least 1987, but there is no evidence that he said these exact words. Orwell wrote in the essay “Notes on Nationalism” (1945):
 
“One has to belong to the intelligentsia to believe things like that: no ordinary man could be such a fool.”
 
British philosopher Bertrand Russell (1872-1970) wrote in “My Philosophical Development” in Encounter magazine (1959):
   
“This is one of those views which are so absurd that only very learned men could possibly adopt them.”
 
   
Wikiquote: George Orwell
George Orwell (25 June 1903 – 21 January 1950) was the pen name of British novelist, essayist, and journalist Eric Arthur Blair.
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Misattributed
There are some ideas so absurd that only an intellectual could believe them.
. Possibly a paraphrase of Bertrand Russell in My Philosophical Development (1959): “This is one of those views which are so absurd that only very learned men could possibly adopt them.” It is similar in meaning to Orwell’s line from Notes on Nationalism (1945): “One has to belong to the intelligentsia to believe things like that: no ordinary man could be such a fool.” However, Russell was commenting not on politics, as Orwell was, but on some philosophers and their ideas about language.
   
Google Books 
Encounter
Volume 12  
1959  
Pg. 18:
Bertrand Russell
My Philosophical Development
Pg. 26:
This is one of those views which are so absurd that only very learned men could possibly adopt them.
   
Google Books
Collected Essays
By George Orwell
London: Secker & Warburg
1961
Pg. 301 (“Notes on Nationalism”):
One has to belong to the intelligentsia to believe things like that: no ordinary man could be such a fool.
 
Google Books
New Society
Volumes 81-82
1987  
Pg. 156:
I was reminded of George Orwell’s statement that there are some ideas so wrong that only a very intelligent person could believe them.
 
2 October 1996, The Intelligencer-Record (Doylestown, PA), “Celebrity Cipher,” pg. D5, col. 4:
PREVIOUS SOLUTION: “There are some ideas so wrong that only a very intelligent person could believe in them.” George Orwell.
 
Google Books
Oxford Dictionary of Humorous Quotations
Edited by Ned Sherrin
Oxford: Oxford University Press
2008
Pg. 169:
There are some ideas so wrong that only a very intelligent person could believe in them.
George Orwell, 1903-1950; attributed
 
Google Books
The Mammoth Book of Great British Humor
Edited by Michael Powell
London: Constable & Robinson Ltd.
2010
Pg. 167:
There are some ideas so wrong that only a very intelligent person could believe in them.
George Orwell