Google the quote, and find the source that you trust. Not hard to believe anyway, after all he's the supposed "vicar of Christ".
Not that I thoroughly scoured the internet in search of a source for this quote, but from what I was able to read, it seems no one has a source for the alleged quote from Pius IX. The most they'll say is "He said in a speech, etc." or "the Vatican Council says, etc." No where do they cite what speech, what document, etc. Furthermore, I can see translation issues becoming a factor here: for instance, Dominus
can mean "Lord" as in "The LORD" or it can mean "Lord" as in "Sir", but I don't trust fundamentalists to make such distinctions, so if they read a Council document referring to a Pope as Dominus noster
, they're already so hellbent against RC's that anything will set them off.
Clearly they are able to cite relevant documents, chapter and verse, when they actually have a solid source to work with; but so far, the veracity of Pius IX saying he's "the Way, the Truth, and the Life" seems to be right up there with the quote from Abraham Lincoln where he talked about not believing everything you read on the internet.