As with all characterizations of any group, there are many examples of exceptions to the rules. That being said, the overwhelmingly most common characteristic of a mathematician is the desire and ability to think logically. That's really about it, except for the fact that, unfortunately, the majority of mathematicians in the world are still male.
Yes, Pythagoras is a mathematician.
mathematician
Mathematician is 'Mathematiker'
pythagorus was a mathematician
Mathematician
yes Mary was a mathematician
A mathematician can be a engineer, an astronaut or a electrician.
mathematician
Yes, George Boole was a mathematician.
mathematician
Edmund LandauArchimedes
Euclid is the great mathematician of all...