I've seen this before but it is worth repeating:
"My son, it is between two wolves...
One is filled with anger, hatred, envy, sorrow, regret, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride, superiority and ego...
The other is filled with joy, peace, love, hope, serenity, humility, kindness, benevolence, empathy, generosity, truth, compassion and faith..."
The grandson thought about it for a minute and then asked his grandfather, "Which one wins?"
The old Cherokee simply replied "the one I feed".