Question: are kagome and kikyo the same person?
Answer: Kagome is the reincarnation of Kikyo. That means that they have the same spirit in a different body. Under normal circumstances ( without Urasue and her magic ) they can't be alive at the same time; however when Urasue brought Kikyo's body back, the soul got torn into two pieces one in Kagome's and one in Kikyo's.