Emotion

Emotion or feeling was a response to an object or a situation that induced either a negative or positive mental state.

Although most species felt at least some kinds of emotions, others did not. The Daleks were deliberately designed by Davros to have no emotions. (TV: Genesis of the Daleks) The Cybermen had no emotions, considering them "weaknesses", and had them removed during cyber-conversion. (TV: The Tenth Planet) This was accomplished by using an emotional inhibitor. (TV: The Age of Steel) However, Kroton was able to regain his emotions. (COMIC: Throwback: The Soul of a Cyberman)

In some societies, emotion was forbidden. The people of the city of Zombus on the planet Zom had their emotions removed on the orders of the Brains Trust. (COMIC: City of the Damned) The Gråttites banned emotion due to the threat of the Mörkön. (COMIC: The Whispering Gallery)

Some species fed on emotion, or certain types of emotion, for sustenance. These included Cerebravores, (COMIC: Revolutions of Terror), Empathivores, (COMIC: The Whispering Gallery) the Fearmonger, (AUDIO: The Fearmonger) the Ilk, (AUDIO: The Forever Trap) the Isolus, (TV: Fear Her) Kharitites, (COMIC: After Life) the Lapino, (PROSE: Planet of the Bunnoids) the Lobri, (COMIC: Ground Zero) Pranavores, (COMIC: Revolutions of Terror) Psionovores, (AUDIO: Minuet in Hell) the Qetesh, (TV: Goodbye, Sarah Jane Smith) the Scourge, (AUDIO: The Shadow of the Scourge) the Shroud (PROSE: Shroud of Sorrow) and the Threckon. (PROSE: Inmate 280)