Jean-Luc Picard: How can I ask them to sacrifice themselves based solely on your intuition?
Guinan: I don't know. But I do know that this is a mistake. Every fiber in my being says this is a mistake. I can't explain it to myself, so I can't explain it to you. I only know that I'm right.
Jean-Luc Picard: Who is to say that this history is any less proper than the other?
Guinan: I suppose I am.
Jean-Luc Picard: Not good enough, damn it, not good enough! I will not ask them to die!
Guinan: 40 billion people have already died. This war is not supposed to be happening. You've got to send those people back to correct this.
Jean-Luc Picard: And what is to guarantee that if they go back, they will succeed? Every instinct is telling me this is wrong, it is dangerous, it is futile!
Guinan: We've known each other a long time. You have never known me to impose myself on anyone, or take a stance based on trivial or whimsical perceptions. This timeline must not be allowed to continue. Now, I've told you what you must do. You have only your trust in me to help you decide to do it.