Naturally, we pursue animalistic behavior - violence is common in history, as is all manner of horrible behaviors towards others. Our animalistic side is deeply tribal, discards the Golden Rule, and acts based on intrinsic feeling.
Some of those aspects of us are helpful; others are harmful. We've enacted our Rights into law, we've embraced our shared humanity in each other, and we've built a global civilization based on shared rules and practices that enable strangers to connect and communicate.
What do we do with those natural parts of ourselves that don't fit in a world of common humanity? How do we channel them?