
Source: "Radio and Television Address to the Nation on the Test Ban Treaty and the Tax Reduction Bill" (18 September 1963) http://www.presidency.ucsb.edu/ws/?pid=9413
2000s
Source: "Radio and Television Address to the Nation on the Test Ban Treaty and the Tax Reduction Bill" (18 September 1963) http://www.presidency.ucsb.edu/ws/?pid=9413
Source: An exploration in the theory of optimum income taxation, 1971, p. 208
2016, Interview with CNBC's John Harwood (August 22, 2016)
2012, " The Fair Tax Isn't Fair, It's a Farce http://www.libertyforall.net/?p=7101"
“The hardest thing in the world to understand is income taxes.”
Attributed by his friend Leo Mattersdorf, who also said that "From the time Professor Einstein came to this country until his death, I prepared his income tax returns and advised him on his tax problems." In a letter to Time magazine, 22 February 1963. See this post from The Quote Investigator http://quoteinvestigator.com/2011/03/07/einstein-income-taxes/#more-2031 for more background.
Attributed in posthumous publications
Source: An exploration in the theory of optimum income taxation, 1971, p. 209
in "Business People; A Nobel Winner Assesses Reagan", The New York Times (1 December 1982)
1980s and later
Source: 1962, Address and Question and Answer Period at the Economic Club of New York