“Politics is the world’s second oldest profession”

Prostitution is often called the “world’s oldest profession.” Ronald Reagan (1911-2004) said in 1975: “I have also learned that politics, which is often called the second oldest profession, has a great similarity to the first.”
 
The association of “second oldest profession” with politics has been cited in print since the 1930s.
 
 
Google Books
The Yale Book of Quotations
Edited by Fred R. Shapiro
New Haven, CT: Yale University Press
2006
Pg. 629:
Ronald W. Reagan
U.S. president, 1911-2004
“Politics is supposed to be the second oldest profession. I have come to realize that it bears a very close resemblance to the first.”
Conference, Los Angeles, Cal., 2 Mar. 1977
 
OCLC WorldCat record
The second oldest profession; a study of the prostitute’s “business manager”
Author: Ben L Reitman
Publisher: New York, Vanguard Press, 1931.
Edition/Format: Book : English
     
Google Books
Saturday Review of Literature
v. 19 - 1938
Pg. 7:
He knows them intimately — politicians — the second oldest profession in the world…
 
Google Books
A Puritan in Babylon:
The story of Calvin Coolidge

By William Allen White
New York, NY: The Macmillan Company
1938
Pg. 260:
...Theodore Roosevelt, who was a gay and happy sprite when he was not one of the devil’s own imps; and McKinley, suave, smooth, diplomatic, a trained politician, the second oldest profession in the world which had for ten thousand years learned the philandering arts of the oldest profession.
       
29 September 1942, Reno (NV) Evening Gazette, “Olin Miller’s Comment,” pg. 4, col. 2:
Now and then we wonder if politics isn’t the second oldest profession in the world.
 
9 September 1944, Reno (NV) Evening Gazette, “Olin Miller’s Comment,” pg. 4, col. 2:
Sometimes we wonder if politics isn’t the second oldest profession in the world.
   
OCLC WorldCat record
The charm of politics; and other essays in political criticism.
Author: R H S Crossman
Publisher: London, H. Hamilton, 1958.
Edition/Format: Book : English
Contents: (...) The second oldest profession -Mussolini and Coolidge
 
28 April 1972, Cleveland (OH) Plain Dealer, “Julian Bond Endorses McGovern in Talk Here” by Richard M. Perry, pg. 13C, col. 2:
In his speech Bond urged the 1,000 teen-agers attending to involve themselves in politics—“my profession, the second oldest profession in the world.”
 
He defined politics as “the art of seeing who gets how much of what from whom.”
 
15 January 1975, Mobile (AL) Register, “Still jogging around track” by William F. Buckley Jr., pg. 6A, col. 4: 
Here was Reagan’s hairshirt, and no one put it better than he when he remarked, only a few months ago, “I have also learned that politics, which is often called the second oldest profession, has a great similarity to the first.”