Newcomb's ABX Model (Theodore Newcomb, 1953)
The first model to treat communication as a social act rather than a transfer. Two people A and B orient toward each other and toward an object X; the drive toward symmetry (co-orientation / balance) — A and B wanting their attitudes to X to agree — is what generates the communication.
Which piece of Shannon it adds back: the relational function, wholly absent from the pipe. Communication exists to maintain equilibrium in a relationship, not to move information. More strain (A and B like each other but disagree on X) produces more communication to restore balance.
Transfer. This explains why agent content that merely informs rarely spreads: sharing is co-orientation. People pass content to align with a group's stance on X — identity, signalling — not because it is accurate. Content engineered as a symmetry move ("here is what people like us think about X") travels; neutral information sits still. Virality is balance-seeking, not fact-seeking, which is why the accuracy of agent output is nearly orthogonal to its reach.
Kin: models, osgood-schramm-circular, spiral-of-silence, growth-stages, two-pleasures-arousal-and-closure