What powers a complex adaptive system? Agency basically means the power to affect a system. Agents are factors that cause a complex system to evolve through their interactions, or "co-evolve", in the case that the system also changes the agent. The more a thing can change a system, the more agency it has.
"Agents" in a system aren't always people. Sometimes they're things, or concepts, or ideas, or subsystems. Sometimes the power to make ripples of change in a system is distributed among many factors--anything from networks of people, to the weather, to political messages. Agents can be relationships or shared stories. Even an idea can have agency. (Ants, apparently, do not--not the individual ants themselves--which makes them useful for studying complex systems.)
To me, the fascinating thing about agency is that its power is derived from the way information flows through networks. So a person might say, "What does my opinion matter? I don't have agency in a system as big as national politics." The level of agency that individual human beings have is debatable.
But ideas spread faster through networks today than in any time in history. The power to change a system or an idea--or the world--can begin with individuals sharing information.
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