One day you finally knew what you had to do, and began, though the voices around you kept shouting their bad advice-- though the whole house began to tremble and you felt the old tug at your ankles. "Mend my life!" each voice cried. But you didn't stop. You knew what you had to do, though the wind pried with its stiff fingers at the very foundations, though their melancholy was terrible. It was already late enough, and a wild night, and the road full of fallen branches and stones. But little by little, as you left their voices behind, the stars began to burn through the sheets of clouds, and there was a new voice which you slowly recognized as your own, that kept you company as you strode deeper and deeper into the world, determined to do the only thing you could do-- determined to save the only life you could save.
I know everyone knows this poem, but it is beautifully written and excellent advice: save the only life you can save, yours.