刚柔相济　

◎ 刚柔相济 gāngróu-xiāngjì

[temper force with grace;the strong and weak mutually assist each other] 刚烈与柔顺相互弥补,柔硬兼施,恩威并用

凡为将者,当以刚柔相济,不可徒恃其勇。——罗贯中《三国演义》