Huge brains helped primates fight via coalition politics, and language let human foragers enforce egalitarian norms against such fights.  If neutrally applied, such norms should have cut the gains to huge brains, yet we had the biggest brains. This suggests hierarchy and coalition politics continued via covert rule bending.  Support for this hypothesis comes from our highly evolved capacities for covert coalitions:

• Body Language – Winks and nods and other body language are not just redundant or complementary to our words. “A wink and a nod” is a common expression for a communication intended to be less visible to third parties, in particular to enable corruption.  Since we are very good at seeing where other eyes look, we can often communicate via the direction of our gaze. Our unconscious status moves include the high status looking directly and the low status looking away; this grants more eye-talk conspiracy power to the high status.

• Indirect Language – When talking with words, we commonly veil our language, instead of speaking directly.  Indirection makes it harder for others to interpret what your mean. So those who are very socially distant, lacking local context, may just not understand, while those closer may understand but be unable to prove what was meant; you’d have plausible deniability.  By varying the indirection of our language we can control how close a circle can understand or prove what we say. Extreme indirection can also signal; if we see that we understand each other, we confirm our intelligence and close connection.

• Rumors – Even when rumors are expressed in direct language, they are not intended for all ears. We explicitly say to not tell certain others, or implicitly understand to only tell a shared coalition. At a minimum, we understand not to tell the subject of the rumor.  Spreading a mild rumor about a person allows us to test how well connected is that person.  If they never complain, perhaps they never heard of the rumor, and so are poorly connected, and thus can be conspired against more easily, perhaps via further rumors.

These skills seem to me too well developed in humans today to have only begun with farming ten thousand years ago.  Compare them to our clumsy farming, war, and writing skills that have to be explicitly taught.  Clearly, foragers had great conspiracy capacities, and so often conspired, bending their egalitarian rules.