A young fawn once said to his Mother, "You are larger than a dog, and swifter, and more used to running, and you have your horns as a defense; why, then, O Mother! do the hounds frighten you so?" She smiled, and said:  "I know full well, my son, that all you say is true.  I have the advantages you mention, but when I hear even the bark of a single dog I feel ready to faint, and fly away as fast as I can." 

No arguments will give courage to the coward.