An old Cherokee was teaching his grandson about life. "A fight is going on inside each one of us," he said to the boy. "It is a fight to the death, and it is between two wolves.
"One is darkness -- he is anger, envy, sorrow, regret, greed, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride, superiority, and ego.
"The other is enlighted -- he is 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 wolf will win?"
The old Cherokee simply replied, "The one you feed."
Assuming that all the offspring survived, 190,000,000,000,000,000,000 flies could be produced in four months by the offspring of a single pair of flies.