The trouble with computers, of course, is that they're very sophisticated idiots. They do exactly what you tell them at amazing speed. Even if you order them to kill you. So if you do happen to change your mind, it's very difficult to stop them from obeying the original order. [stops computer from destroying Earth] But not impossible.
“Robot” · Season 12, Episode 1
In this episode: Fourth Doctor (14), Sarah Jane Smith (5), Brigadier Lethbridge-Stewart (5), Harry Sullivan (5)
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