Every human actions becomes dangerous when it is deprived of human feeling. When they are performed with feeling and respect for human values, all activities become constructive.
When you were born you were crying and everyone else was smiling. Live your life so at the end, your're the one who is smiling and everyone else is crying.
Since you cannot do good to all, you are to pay special attention to those who, by the accidents of time, or place, or circumstances, are brought into closer connection with you.