"Bruce Wayne is Batman. He became Batman the instant his parents were murdered. Batman needs Bruce, however hollow that identity feels to him from time to time. Bruce keeps Batman human"

This quote by Kevin Conroy talks to the duality of Bruce Wayne and Batman. Bruce Wayne is the man behind the mask, and Batman is the symbol of justice and hope. Bruce Wayne became Batman the minute his parents were killed, and he has actually been living with this double identity since. Batman requires Bruce to stay human, to keep him from ending up being a sign of revenge and hatred. Bruce Wayne is the one who keeps Batman grounded and advises him of his humanity. Regardless of the truth that Bruce Wayne might feel hollow and empty sometimes, he is the one who keeps Batman from becoming a sign of darkness.