Comment: The envious caveman serves no productive purpose.

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The envious caveman serves no productive purpose.

An envious caveman can't figure out how to make his own spear. Perhaps he's just too lazy? Perhaps he sees it as a dominance issue and doesn't think somebody else, somebody less than him should have something he doesn't? Maybe he's a flee bitten caveman moocher who doesn't know how to produce ANYTHING of value, and feeds off the group, knowing he has nothing to trade you for a spear of his own?

For whatever reason, that unarmed and envious caveman knows he needs THAT spear; YOUR SPEAR, and if he can't figure out how to get it from you, he'll kick it into the fire while you're not looking. (The fire you showed him how to make.)