"What is the virtue in feeling sad? When you are feeling sad, you are
regretting something. You are lonely for someone or something. It is a
mourning. Perhaps you regret that you didn't enjoy another Being more when
he or she was right here before you. And so you enjoy them now with your
sadness."
I was writing something for people who have difficulty dealing with loss of their beloved pet. I added this. Yes you are quoted with other notable authors. Of course God is your ghost writer and I explained that too.