Spock: Captain. This afternoon you wanted to kill.
McCoy: But he didn't kill, Mr. Spock.
Spock: But he wanted to, Doctor.
Kirk: Mr. Spock, you're exactly right.
Spock: Mankind... ready to kill.
Kirk: That's the way it was back in 1881.
Spock: I wonder how humanity managed to survive.
Kirk: We overcame our instinct for violence.