@Igor Yes, quid is right. I wanted to stress the difference between questions that I would personally answer and questions that might better be not answered here. If a colleague asked me why the neutral element of a group is unique, I would be rather surprised, but I would of course answer him. I would, however, not expect this kind of question to be answered on this site.

But then, I assume you would also not say about yourself that the purpose of your existence is for discussing research level mathematics.

@Bill. What you point out is interesting (I do not work in the Sates, though), but I hope its not meant as a counterargument to what I said. Just because there is lack of privacy in one area does not mean that I willingly give it up everywhere.