....what does it say on your degree certificate?
Sounds daft, but I never paid too much attention to mine when I received it at the grad ceremony, it got put away in it's envelope.
However, recently I had to supply a copy of it to someone ... I looked closely and am surpised that it just says "This is to certifiy that on {date), Kronk o'Dile was admitted to the degree of Doctor of Philosophy."
There's no indication of what subject it was in, what department I was in, etc, nothing. That's it. Are they all like this? I could say I've got a doctorate in anything if the certificate is taken at face value!