“America is the most grandiose experiment the world has seen, but, I am afraid, it is not going to be a success.”

Source: 1980s, Trump: The Art of the Deal (1987), p. 46

Nothingness
Source: "I am That." P.88.

I believed from my first attack that I should not survive it — my breath cannot last long.
The first sentence here is sometimes presented as being his last statement before dying, but they are reported as part of the fuller statement, and as being said in the afternoon prior to his death in Life of Washington (1859) by Washington Irving, and his actual last words are stated to have been those reported by Tobias Lear below.
1790s

Source: Red Glove

Source: Striking Thoughts (2000), p. 22

Interview with Luxemburger Wort (2015)

Personal communication (4 April 2006) quoted in "Well, someone has to do it" at Moment of Science (July 2006) http://momentofscience.blogspot.com/2006/07/well-someone-has-to-do-it.html
Context: I am afraid that those comments go back to the late 80's. At that time I was a skeptic — the argument based on Koch's postulates to try to distinguish between cause and association. … Today I would regard the success of the many antiviral agents which lower the virus titers (to be expected) and also resolve the failure of the immune system (only expected if the virus is the cause of the failure) as a reasonable proof of the causation argument

Shah of Iran state visit to the USA, 1961 http://www.youtube.com/watch?v=K1a5TAepYXs,
Interviews

As quoted in "Cosmo Listens to Records" http://www.mediafire.com/view/za1l4i1dftotwg9/.png by Nat Hentoff, in Cosmopolitan (November 1965)