So how do you invoke fear at will
Practice.
, how do you invoke resentment or boredom, etc, at will
Boredom? lol! It’s gotta be hours and hours of tons of fun for some people, to practice emulating the internal experience of boredom, its physiological and emotional symptoms, associated breathing and heart rate…surely one can hardly be bored with so much to focus on!
..and why would you want to?
Seriously - to enable me to reduce my own reactivity to circumstance, thereby making me a happier, more effective person. It is really the only thing I
can control, to the extent that I actually do (assuming it’s not only an illusion of control, since I can get what I want, but can’t want what I want).