Q: You said you regretted a great many things in your life. Well, here's a chance to change some of them.
PICARD: Change them? You mean change the past? Q, even if you have been able to bring me back in time somehow, surely you must realize that any alteration in this timeline will have a profound impact on the future.
Q: Please, spare me your egotistical musings on your pivotal role in history. Nothing you do here will cause The Federation to collapse or galaxies to explode. To be blunt: You're not that important.
[In a show of anger, Q sweeps his riding crop across the chess set he's been playing with, scattering the pieces on the floor] Q: Very well! Since you attach so much importance on the continuity of time. [He stands and gets to Picard's face] I will give you my personal guarantee that nothing you do here will end up hurting anyone or have an adverse effect on what you know of as history. The only thing as stake here is your life and your piece of mind... Now... Whether you believe me or not you are here and you have a second chance. What you choose to do with it is up to you. Do you know where you are?
PICARD: Starbase Earhart. We came here right after graduation to await our first deep space assignments.
Q: That's right. It's two days before your unfortunate encounter with a Nausicaan sword. You have that long to make whatever changes you wish. If you can avoid getting stabbed through the heart this time, which I doubt, I will take you back to what you think of as the present. And you can go on with your life with a real heart.
Q: I'm glad you think so. I am curious about one thing, Johnny. Why did that rather attractive woman strike you just now? Something you said?
Picard: Her name was Corlina. I'd arranged to take her out today, and then she discovered that I had already made a second date with another woman called, er, Penny, and Corlina was naturally upset.