As long as we're talking psychology...

...you probably oughta read this piece. Offers insight into hostilities, whether on the playground or in the Middle East.

He Who Cast the First Stone Probably Didn’t

By DANIEL GILBERT
Published: July 24, 2006

LONG before seat belts or common sense were particularly widespread, my family made annual trips to New York in our 1963 Valiant station wagon. Mom and Dad took the front seat, my infant sister sat in my mother’s lap and my brother and I had what we called “the wayback” all to ourselves.

In the wayback, we’d lounge around doing puzzles, reading comics and counting license plates. Eventually we’d fight. When our fight had finally escalated to the point of tears, our mother would turn around to chastise us, and my brother and I would start to plead our cases. “But he hit me first,” one of us would say, to which the other would inevitably add, “But he hit me harder.”

It turns out that my brother and I were not alone in believing that these two claims can get a puncher off the hook. In virtually every human society, “He hit me first” provides an acceptable rationale for doing that which is otherwise forbidden. Both civil and religious law provide long lists of behaviors that are illegal or immoral — unless they are responses in kind, in which case they are perfectly fine.

After all, it is wrong to punch anyone except a puncher, and our language even has special words — like “retaliation” and “retribution” and “revenge” — whose common prefix is meant to remind us that a punch thrown second is legally and morally different than a punch thrown first.

That’s why participants in every one of the globe’s intractable conflicts — from Ireland to the Middle East — offer the even-numberedness of their punches as grounds for exculpation.

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