Tuvok: (after Kes' powers severely injure Tuvok) You are probably feeling the emotion known as remorse. Possibly guilt. I advise you to look on this incident as a learning experience.
Kes: It's not that easy. I almost killed you.
Tuvok: That is correct. But you did not. Try to remember that.
The Doctor: Vulcans make the worst patients.
Tuvok: Without the darkness, how would we recognize the light? Do not fear your negative thoughts. They are part of you. They are a part of every living being. Even Vulcans.
Tuvok: The Vulcan heart was forged out of barbarism and violence. We learned to control it, but it is still part of us. To pretend it does not exist is to create an opportunity for it to escape.
Guest star Gary Graham was considered for both the roles of Captain Benjamin Sisko on ST: DS9 and Captain Janeway on Voyager.
An early working title for this episode was "Untitled Kes Firebug".