Hope

Hope was an emotion which the Twelfth Doctor claimed was hard to resist. (TV: The Eaters of Light)

After the death of Lucie Miller, the Eighth Doctor found himself looking for hope. (AUDIO: The Great War)

While the Tenth Doctor conceded to Cyber-Leader One that emotions were an ultimately destuctive flaw, he retorted that he "quite like[d]" hope, calling it a "good emotion" as he indicated to the Cyber-Leader that it was coming. Indeed, as soon as the Doctor spoke, Jake Simmonds and the Preachers arrived from Pete's World and terminated the Cybermen holding the Doctor captive. (TV: Doomsday)

When Kenossium told the Eleventh Doctor that the Time Lords would have nothing should he place Gallifrey in a pocket universe, he responded that they would have hope, something which they currently did not possess. (TV: The Day of the Doctor)