Don't I know it!
It all depends on how specific or general the statement is. It is a fact the "nothing", the word itself, is written, or chiseled, in that specific stone. Of course I am having fun but in a literal and very specific case I the statement is correct.
What a great sense of humor!
That is funny!
This is actually a mistelling of the phrase I was taught. It is stupid to say, "nothing is written in stone." (Ha-ha) We all know that the Ten Commandments were written in stone. I was taught that the phrase is spoken as a response to some conventional wisdom, and it goes more or less like this: Yadayadayada, and then you say, "Well, ("well" is very important here!) it's not like it's written in stone or anything..." Meaning, whatever your concern is, it's not as important as the Commandments.
What was really funny is that all the broadcast said to me was, "Your oxymoron for the day." Did I miss a good one?
I think that properly speaking this is irony rather than oxymoron, which is a combination of two seemingly contradictory terms to convey a single idea, e.g. "O happy fault!" (Supposedly, it was Wm. F. Buckley who started the widespread misuse of "oxymoron" back in the 1960's.)
ox·y·mo·ron [ok-si-mawr-on, -mohr-]–noun, plural -mo·ra [-mawr-uh, -mohr-uh] a figure of speech by which a locution produces an incongruous, seemingly self-contradictory effect, as in “cruel kindness” or “to make haste slowly.”
One of my favorites...in women's dress sizing labels: petite large!( There are also small and mediums sizes in petite category.)
In this case nothing is written in stone. I believe the metaphore is things change. The sentence; "Nothing is written in stone" is predicated on the verb "is (to have actuality or reality)."
A comma after the word "nothing" would change the whole meaning of this saying.