Board Thread:The Panopticon/@comment-26975268-20130407222910/@comment-4189499-20130415032311

Be aware he used the word "world", not planet. World has a slightly wider definition, which in this case is most likely referring to the planets and their populations, which makes more sense because planets can't have beliefs. They're planets. It's the people on those planets which have those beliefs. It is implied in that line, at least to me, that the Doctor is referring to a religious belief of the people who inhabit the 7 planets, and that the people who hold that belief are called the Sun Singers of Akhet, like the people who believe in Christianity are called Christians and the people who believe in Judaism are called Jews.