此時為敵，彼時為友 Enemy at This Moment, Friend at That Moment

人之言行，固有百態。	People speak and act in various ways.
以一部善而全善之，不智。以一部惡而全惡之，不智。	It is not a wise decision either to accept everything of one person for his single good deed, or to refuse everything of one person for his single bad deed.
以一時善而恆善之，不智。以一時惡而恆惡之，不智。	It is not a wise decision either to accept one person forever for his good deed at one moment, or to refuse one person forever for his bad deed at one moment.
隨時觀察，應為敵時，敵之；應為友時，友之，始為正解。	We shall always treat one person as our enemy when he is detrimental to us, and as our friend when he is beneficial to us, based on our real-time observation.