...My dad, may he rest in
peace, taught me many wonderful things. And one of the things he taught me was never ask a guy what you do for a living.

He said "If you think about it, when you ask a guy, what do you do you do for a living," you’re saying "how may I gauge the rest of your utterances." are you smarter than I am? Are you richer than I am, poorer than I am?"

So you ask a guy what do you do for a living, it’s the same thing as
asking a guy, let me know what your politics are before I listen to you so
I know whether or not you’re part of my herd, in which case I can nod
knowingly, or part of the other herd, in which case I can wish you dead.

Autore: David Mamet