Question about Salazar Slytherin and Voldemort

Rating: Null/10 (11 August 2006)

I don't know if this was posted before, but in this movie we learn that Salazar Slytherin was very particular about the students that he wanted "only pure bloods in Hogwarts", but when Harry enters the chamber of secrets and finds Tom Riddle and he describes himself as Lord Voldemort he specifically said "Surely I wasn't going to keep my filthy muggle mother's name" so that means that Lord Voldemort is not a pure blood, that he is a muggle himself, maybe he really wasn't the true heir of Salazar Slytherin, maybe he performs a spell or a curse on the basilisk so that he can controlled it. So who really was the true heir of Salazar Slytherin I just hope that since harry can speak parcel tong that he isn't the heir of Slytherin and that is what Harry Potter is. Also in the book of JK Rolling they talk about the prophecy of a boy or something like that maybe the prophecy talks about that Harry Potter is the heir of Salazar Slytherin and is related to Lord Voldemort I just hope that is not true. What do you all think?