I'm listening to Michael Thomas Spanish (disc 3, episode 6) and learning Castilian Spanish.
In this he explains the characteristics between ser and estar, which I thought I'd understood - ser is a constant characteristic and estar is a current characteristic.
An example from the CD is Pablo está bien vestido hoy - I understand why it's from the verb estar and not ser! He's only well dressed today.
However, at the end of the track, he asks a student to translate
I am a professor
and he said it was
This is where I'm confused. We can change jobs and as such, I would have thought Estoy professor is more accurate? Or would this statement imply you're about to change job?
My question is why is it soy? Is it just an exception to my understanding (as defined above) or is my understanding between the 2 verbs incorrect?