Define higher self.

Your true Self, sometimes called the higher self, is the immortal part of you. It is almost totally obscured by the most dominant feature of your human personality, the mortal Ego. To obtain immortality with your memory and individual identity intact you must download your personality into the immortal Self. To do this the Ego must die. Its going to die anyway, but so are you if you let it remain in charge. All doctrines and disciplines teach this, including Christianity. You just need to know where, and how, to look.