“Nothing about this entire scenario made sense. But who cares? Once in a while, everyone was entitled to be a bit flaky, and now it was his turn.”

"Concealment and Exposure".

Quoted in Robert Sobel's review of Past Imperfect: History According to the Movies edited by Mark C. Carnes.
Quoted in Timothy J. Penny, http://www.nationalreview.com/article/207925/facts-are-facts-timothy-j-penny, National Review September 4, 2003.
Ellen Hume, Tabloids, Talk Radio and the Future of News, part 4 http://www.ellenhume.com/articles/tabloids4.html ( TOC http://www.ellenhume.com/articles/tabloids_contents.html), 1995 cites this as something Moynihan said to a "1994 electoral opponent on WNBC in New York".
However, proceedings http://web.archive.org/web/20141031220947/http://www.intelligence.senate.gov/pdfs/96id_protection.pdf of a Senate Intelligence Committee in 1980 attribute the identical quote to James R. Schlesinger (at p. 110), possibly made during the course of 1973 Congressional testimony.
Also see Bernard Baruch, who said "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." in the January 6, 1950 issue of the Deming (New Mexico) Headlight
See also this Barry Popik blog http://www.barrypopik.com/index.php/new_york_city/entry/everyone_is_entitled_to_his_own_opinion_but_not_his_own_facts for some etymological research into this quote and its variants.
Attributed
Variant: Everyone is entitled to their own opinions, but they are not entitled to their own facts.
Variant: You are entitled to your own opinion, but you are not entitled to your own facts.
Variant: You’re entitled to your own opinions. You’re not entitled to your own facts.

"The Contest in America," Fraser’s Magazine (February 1862); later published in Dissertations and Discussions (1868), vol.1 p. 26
Context: War is an ugly thing, but not the ugliest of things: the decayed and degraded state of moral and patriotic feeling which thinks that nothing is worth a war, is much worse. When a people are used as mere human instruments for firing cannon or thrusting bayonets, in the service and for the selfish purposes of a master, such war degrades a people. A war to protect other human beings against tyrannical injustice; a war to give victory to their own ideas of right and good, and which is their own war, carried on for an honest purpose by their free choice, — is often the means of their regeneration. A man who has nothing which he is willing to fight for, nothing which he cares more about than he does about his personal safety, is a miserable creature who has no chance of being free, unless made and kept so by the exertions of better men than himself. As long as justice and injustice have not terminated their ever-renewing fight for ascendancy in the affairs of mankind, human beings must be willing, when need is, to do battle for the one against the other.

"Unlikely heir who saved the family jewels" http://www.ft.com/cms/s/0/0693507a-4830-11e0-b323-00144feab49a.html#axzz1GZU7VVRA, Financial Times, 03-06-11

Jean-Michel Jarre, Edward Snowden - Exit, 2016 https://www.youtube.com/watch?v=YNESMafb5ZI
2015

Source: Boneshaker (2009), p. 41

Source: Wicked Intentions

Source: Flipped (2001)