**SPOILER WARNING** (for those who haven't watch Star Trek: The Final Frontier)
Well, I just remember ST:TFF. In the movie, the Vulcan Sybok (who happened to be Spock's brother) recruited followers by removing their pain. Yes, emotional pain, childhood trauma, etc. Then, after boarding the Enterprise, Sybox also "recruited" Kirk's crew by the same method, and eventually the officers too. Doctor Bones suffered an endless self-guilt for secretly performing euthanasia on his dying father, and Sybok removed the pain. Spock also suffered the pain of being an outcast (being half-human and such), and Sybok removed the pain too.
And eventually, it was Kirk's turn. But Kirk refused; saying that pain is actually part of us --the thing that makes us who we are, and if we lose the pain, then we actually lose ourselves.
Here's from the movie script
I think Kirk could have other, stronger reason of not wanting Sybox to remove the pain, because Sybox had hidden intention of taking over the Enterprise (to bring him to "God").KIRK: About what? Thay I've made the wrong choices in my life? That I went left when I should've gone right? I know what my weaknesses are. I don't need Sybok to take me on a tour of them.
McCOY: If you'd just unbend and allow yourself --
KIRK: To be brainwashed by this con man?
McCOY: I was wrong. This "con man" took away my pain!
KIRK: Dammit, Bones, you're a doctor. You know that pain and guilt can't be taken away with the wave of a magic wand. They're things we carry with us -- the things that make us who we are. If we lose them, we lose ourselves. I don't want my pain taken away. I need my pain.
But now here's the question: if Sybox offers to remove your pain just for the sake of it (not taking over your ship, not recruiting you as his follower, etc), would you accept? Would you like to have your pain and trauma removed? Or would you rather agree with Kirk, that our pain is actually what made us, and removing our pain means losing ourselves?