On a country road in the middle of the 15th century England, the Doctor and Clara discuss about the implications of being a Time Lord.
Clara: You said your people could control time and space...
The Doctor: Yes...
Clara: So... does that make them gods?
D: They liked to think that way, but no.
C: Why not? They could live forever, control history and destiny...
D: They weren't because there are laws of time they could not manipulate.
C: So who wrote those laws? Are there others with those capacities? And why can't you just change the rules?
D: I can't, no one can! The laws are just there, only existing.
Clara (confused): But why?
D(taking a small rock off the road): Look: do you know why this rock falls?
C: Because it is pulled down by the Earth's gravity field!
D: And do you know why the is any gravity field?
C: No...but...
D: But nothing, you don't know, not yet anyway...
C: But you do know!
D: Obvious.
C: So there is an explanation. If there is one for gravity there must be one also for the time rules. Don't you wanna find it?
D: No.
C: Why not? This way you can really become God!
D: But I don't want to be God!
C: Because...
D: Why would I?
C:Control...I dunno...stuff?
D: See...I don't need any more stuff, I've got plenty of it already.
C: To make a perfect Universe!
D(laughing): There is no such thing as perfection through a living being's eyes. Perfection is defined by perception and only living beings can have some perception over their world. The solely perfect thing is death. Something not living can't complain about flaws so there are no flaws, so everything is perfect. See, if you go that way I could create a perfect Universe by simply killing everyone in this one. Not that much fun afterwards. The wonder is in the variety because every imperfection makes individuals unique. The world is amazing just the way it is if you just open your eyes and see, really see.
(deep silence)
C: But you still try to make it better. You're a hero!
D (sad smile): I'm just a mad man in a box... You can't judge madness. It's irrational and doesn't follow the general belief...I'm not a reference, I'm alive!