§ IImage
Cooperation (συνέργια) is not a moral ideal but a constitutive feature of the rational nature. The image of "working-together" tools or organs makes cooperation not a choice but a function: bees for the swarm, sheep for the flock, rational beings for one common task. Every withdrawal from cooperation is therefore not "a failure in virtue" but self-dissolution: that which has left the common work becomes useless both to the whole and to itself.
§ IISource
Med. 2.1 (the end of the passage); 5.16 ("what does not harm the city does not harm the citizen either"); 6.42 ("we are all cooperating in a single work — some consciously, others unwillingly… see that you are among the first"); 7.13; 9.23 ("every action that does not relate directly or indirectly to the social end tears one's life apart"). The Greek background: Aristotle Pol. I 2 (the human being as ζῷον πολιτικόν, the political animal), reinterpreted by the Stoics in the terms of DOGMAoikeiosis and the community of the Logos.
§ IIIUsage
In 02-01 the image of cooperation is the positive norm that throws into relief the negative diagnosis of TERMcounter-action. The structure of the argument: (1) the TERMnature of rational beings is cooperation; (2) anger and estrangement are its rupture; (3) therefore anger is contrary to nature. The image is paired with body-parts — there cooperation is shown through the organs; here the emphasis is on its teleological sense. See TERMsynergia as the term and DOGMAunity-of-cosmos as the ontological foundation.