Re: 7X07 The Rings of Akhenaten (Grading/Discussion) (SPOILERS!)
The Three Doctors or Castrovalva.
Mr. Light wrote:
What episode was the Doctor referencing when he said he's seen a universe created at the whims of a madman?
"Of all the so-called natural human rights that have ever been invented, liberty is least likely to be cheap and is never free of cost.”
- Robert Heinlein, Starship Troopers