The Christmas Invasion - S2-E2
Doctor: These human beings. Consider their potential. From the day they arrive on the planet and blinking step into the sun. There is more to see than can ever be seen. More to do than - no, hold on...Sorry, that's 'The Lion King'. But the point still stands. Leave them alone!
The Christmas Invasion - S2-E2
Doctor: See, there's the thing. I'm the Doctor, but beyond that, I - I just don't know. I literally do not know who I am. It's all untested. Am I funny? Am I sarcastic? Sexy? Right old misery? Life and soul? Right-handed? Left-handed? A gambler? A fighter? A coward? A traitor? A liar? A nervous wreck? I mean, judging by the evidence, I've certainly got a gob.
Chosen answer: The Master knows that deep down, he deserves death for the crimes that he's committed throughout his life, and since he regards The Doctor as his arch-foe, he expects it to be at his hands. The fact that The Doctor is still willing to forgive him for all of his crimes hurts him more deeply than death would.
Captain Defenestrator