This blog is about the book How The Irish Invented Slang by Daniel Cassidy. I became so annoyed at the way that this book is spreading lies and misinfomation about the Irish language that I decided to set up a blog to tell the truth about Daniel Cassidy and his ridiculous theories. I have covered a good proportion of the hundreds of words in Cassidy’s book, explaining why they are nonsense and pointing out his poor methodology and outright dishonesty. In the course of writing the blog, I was also tipped off by Cassidy’s sister that Cassidy failed to get his degree from Cornell, and this has been confirmed by the Registrar of that institution. This means that far from being a real Professor, Cassidy had no academic qualifications at all and was a total fraud. Unfortunately, Cassidy had a large number of friends who were credible academics and writers and these friends have supported this rubbish with positive reviews, so many gullible people have been fooled into thinking that there is some truth to Cassidy’s ideas.