There was a certain army doctor, whose job was to accompany soldiers to battle and tend to their wounds  on the battlefield. But it seemed like every time he patched someone up, the soldier would just go right back into battle and end up being killed. After this had happened over and over again, the doctor finally broke down. If it’s their fate to die, why should I try to save them? If my medicine means anything, then why do they go back to war and get killed? Not understanding what significance there was in being an army doctor, he felt extremely confused and couldn’t go on with his work. So he went into the mountains in search of a Zen master.

After studying with the Zen master for several months, he finally understood his problem and descended the mountain to continue his practice. When troubled with doubts thereafter, he simply said: “Because I’m a doctor!”
Don’t project your self on things you come into contact with, and don’t differentiate between yourself and other things, because so-called subjectivity and objectivity do not exist. The domain of wisdom is in understanding that there is no self, there is no other, and everything is the way it is. (From Zen Stories: The Staff and Shout of the Venerable Ones)