In December 2015, I wrote a post (The Tyranny of Narrative) in which I questioned Cassidy’s story about how his ludicrous book How The Irish Invented Slang came to be written. As I explained in that post, there are a number of reasons for doubting Cassidy’s claim that he came up with his theory after inheriting a pocket Irish dictionary and noticing words in Irish which were similar to English slang terms. For one thing, Cassidy’s sister Susan doubted its truth. Then there is the fact that Cassidy was a pathological liar and that very little of what he said and wrote is trustworthy. And then again, there is the fact that Cassidy’s little origin myth about the pocket dictionary (which he insisted on calling a Folklore Poker rather than a foclóir póca) exists in two different forms. Plus the fact that the words which Cassidy claimed to be examples of the similarities he had spotted are mostly obscure terms which don’t occur in the pocket Irish dictionary he inherited.
Anyway, in another post (Cassidy’s Plagiarism) I also pointed out that many of the more believable (though none the less wrong) claims in Cassidy’s book had already appeared on an Irish language forum called the Daltaí Boards in 2004. Cassidy joined this forum and bothered people with his nonsense for a while in 2005 but of course, he may have read it many times before he joined. I suggested at the time in the comments that Cassidy perhaps derived his theory not from the pocket dictionary, but from reading the posts on the Daltaí Boards.
Recently, I had another look at this question and decided to find out when the earliest evidence of Cassidy’s ‘research’ can be found online. I found that Cassidy wrote an article in the NY Observer (standing in for his crony Terry Golway) in January 2003 about the links between criminal cant and Irish. If he had already posted in 2003, then plainly, he wasn’t influenced by the posts about Irish influence on the Daltaí Boards. However, there was something that just didn’t sound right to me, so I decided to check the Daltaí Boards again.
It turns out that the exchange in 2004 wasn’t the first discussion of words of Irish origin in English on the Daltaí Boards. There was an earlier exchange in April 2002, in which a number of terms were discussed, including shanty, slew, slogan, trousers, smithereens, galore, kybosh, whiskey, leprechaun, banshee, bard, bog, brogue, colleen, glen, jockey, keen, pet, so long, phoney, longshoreman, do you dig?, spree.
So, what’s the real story about Cassidy’s ‘epiphany?’ It seems to me that the story about the pocket dictionary is full of holes. Perhaps Cassidy noticed one or two words that other people have mentioned before (like snas and snazzy) but I think it was his surfing on Google that really gave him the first claims for his book. And then he went on the rampage with his own imagination, inventing hundreds of nonsensical Irish phrases like bocaí rua and gruaim béil and sách úr and leathluí géag and gus óil to fill his book up and turn it into the collection of total garbage which has polluted the world’s libraries and bookshelves ever since.