Star Trek: Voyager1995

Kes:
To be honest, I never want to see that part of myself again.

Lieutenant Tuvok:
To which part are you referring?

Kes:
To the part of me that got pleasure from destroying those plants in the airponics bay. To the part of me that was tempted to go with Tanis. I never realized I had such dark impulses.

Lieutenant 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.

Kes:
You?

Lieutenant 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.