I didn't make any affirmation. I don't know what the criteria are for coming under the heading "mathematician". I would count an undergraduate degree as adequ

I didn't make any affirmation. I don't know what the criteria are for coming under the heading "mathematician". I would count an undergraduate degree as adequate -- but he is 20; he does not call himself a mathematician; he says rather that he is 'passionate about mathematics, mathematical exposition and programming'. One could also study the internal evidence of the post.