no one in his/her/their right mind would (do something)
No one who is sane would consider doing something; someone would have to be crazy to do something. All I'm saying is that no one in their right mind would ask the boss for a raise with the economy the way it is right now. Everyone knows Jake is a mess—no one in her right mind would date him.
nobody in their right mind
or no one in their right mind
COMMON If you say nobody in their right mind or no one in their right mind would do a particular thing, you mean that it is a stupid or crazy thing to do. No one in their right mind would go travelling on their own in such a dangerous region. Note: You can also say who in their right mind? with the same meaning. Who in their right mind would give information like that over the phone?