Now Cain talked with Abel his brother; and it came to pass, when they were in the field, that Cain rose up against Abel his brother and killed him.
Genesis 4:8, NKJV

Cain and Abel were born to the same parents, grew up in the same location, received the same education, and shared the same skin color. They could not blame society for their actions. No society existed. They had no heritage of privilege or oppression. They did not even have grandparents. Granted, they were the first to inherit a sin nature, and they must have had a complicated relationship with their sisters. But in the second generation of the human race, Cain obliterated the popular notion that violence is rooted in environmental factors beyond our control. The simple truth is that Cain’s tragic murder of Abel did not result from outside forces, but from sinful, jealous anger raging within. The road to peace is paved with individual hearts changed by the love of God.