The Evolution of Agency: Behavioral Organization from Lizards to Humans

Michael Tomasello

My review 2022-12-19

Michael Tomasello is an unusual scientist who does not shy away from the big questions. His new book is short and written with admirable clarity. He marshals both empirical and philosophical evidence to support his hypothesis on the evolution of agency in animals. Agency is the active approach that higher animals take to the problem of surviving. The paradigm of stimulus/response that is sometimes used to analyse this activity is hopelessly inadequate, in Tomasello's view. He posits a number of stages in the evolution of agency, where humans have reached the stage of socially normative agents, in which culture and norms are an essential part of our ecological niche.

A basic building block for all kinds of agency is the feedback control model. The organism has goals, and it monitors the environment and its own actions to improve the attainment of those goals. The basic driving force for the evolution of higher levels of agency was the increase in uncertainty in the environment due to competition and predation from other animals. A kind of arms race ensued. With each stage in the evolution of agency, another level of control is added at a higher level.

The first stage of agency involved flexible, context-sensitive behavior and learning, and involves attention to goal-relevant situations. The early vertebrates, modeled by current lizards, are hypothesized to have this level of goal-directed agency.

The next level, intentional agents, was probably reached by ancients mammals, corresponding to modern squirrels and rats. Due to increased competition with other goal-driven animals (including its own species and group), the ability to form a plan, an intention, evolved. This meant a degree of control of the lower-level goal-oriented behavior, adding more room for learning. An executive tier of decision-making and cognitive control was the means.

The third level reached by the ancient apes, probably similar to today's chimpanzees, was that of rational agents. By comparing plans and simulating in the mind various alternative actions, apes could begin to act logically and reflectively. The benefit to the individual was to understand how and why other individuals (conspecifics) acted as they did, and to anticipate their future moves. This required another executive tier, the reflective tier, which made it possible for apes to attribute mental states to others. An understanding of causality was also part of this development.

And finally, the fourth stage, ancient humans. Here new levels of social interaction, collaboration and competition became the driving force for development of joint agency in collaboration. Two persons agreeing to act together in a task, entailing commitment and role-taking. The collaboration of humans became obligate, i.e. it became a necessary mode of life. The selection for cooperatively competent and motivated individuals became very strong. Self-regulation in this social collaborative environment became essential, and the urge to make others conform developed as a response. Norms were born. Another level of executive control was added to regulate joint agency.

Culture, morality and collective agency thus evolved out of the need for better collaboration. "Human social relationships in general ... derive from the fundamentally cooperative nature of human social relationships." Once culture became important, it drove evolution by making cultural groups into coherent units of natural selection. Modern cultural groups have become collective agencies. This in turn explains the very strong in-group/out-group psychology of humans.

The need to look out for our individual interests, at the same time as we want to collaborate with others, is the fundamental reason why we humans experience true moral conflicts. We inhabit an objective-normative world, where norms are human creations, and yet have objective existence.

I find Michael Tomasello's hypothesis to be bold and extremely interesting. It makes sense of, and puts into perspective, the importance that norms and culture have for humans. The role of evolutionary thinking in social, political and ethical thinking is clearly growing.