There is an old Cherokee story that goes as follows.  An elder was talking to young child and said:

“A conflict is going on inside of me…it is a terrible fight and it is between two wolves.  One of them is filled with anger, envy, sorrow, regret, greed, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride and superiority. The other wolf is joy, peace, love, hope, serenity, humility, kindness, benevolence, truth, compassion and faith.  This same fight is going on inside of you…and inside of every other human too.”

The child thought about this for a moment and then asked his elder, “Which wolf will win?” The elder simply replied:  “The one you feed…”