evidence: The Facebook post showed a "false information" label that linked to a fact check from Lead Stories. The author of that 2019 fact check called the quote "fake" and referenced TwainQuotes.com, an authoritative source of researched quotes from Twain's writings. TwainQuotes.com did not feature the quote in question in its collection. The Australian Associated Press (AAP) fact-checking website also once published a story about the quote. According to the article, a museum spokeswoman for the Mark Twain House & Museum in Hartford, Connecticut, said that its staff found "no trace" that would support attribution of the quote to Twain. [...] Also, in a letter dated March 23, 1898, Twain, referred to by his real name, Clemens, wrote to wealthy businessman Henry Huttleston Rogers, saying that, "Circumstantial evidence is among the most valuable of all testimonies." The letter appears on page 336 of the book, "Mark Twain's Correspondence with Henry Huttleston Rogers, 1893-1909."