This chapter draws together many of the themes developed separately in earlier chapters. Co-operative action – building new action by decomposing and reusing with transformation resources provided by earlier actors – underlies many phenomena typically examined in isolation from each other in separate disciplines: language, social organization, technology, our ability to share knowledge and experience by inhabiting each other’s actions, the distinctive character of human cooperation, cognition able to incorporate the contributions of others and path-dependent accumulation of diversity in language, culture, tools, and settings that creates pedagogy, or more generally, the task faced by each community of building new competent inhabitants. Rather than being constituted in a single domain, action is built by collecting together different kinds of materials into arrangements of mutual elaboration. Unfolding time as lived practice is central to this process on all scales, from within noun phrases to the historical diversification of societies. The task of accomplishing mutual intelligibility so as to rapidly build next action creates an environment that would promote the emergence of Peircean symbols, themselves forms of co-operative action, in the natural world. Co-operative action’s transformation of history, cognition, and sociality is central to the human adaptation.

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