Andre Gide Irreplaceable Quotations

Do not do what someone else could do as well as you. Do not say, do not write what someone else could say, could write as well as you. Care for nothing in yourself but what you feel exists nowhere else. And, out of yourself create, impatiently or patiently, the most irreplaceable of beings.

Every instant of our lives is essentially irreplaceable: you must know this in order to concentrate on life.