Abstract
Externalist theories of teleology are views that explain the actions and ends of living beings in terms of nonnormative phenomena. “Field theory” (FT) adds to them that teleology arises from external guidance. Embracing an artifact model, it considers all systems as functional by-products of their field relationships, whether these are internal or external to an organization. The key categories to understand how they do this are persistence (the tendency of an entity to return to the same trajectory after being perturbed) and plasticity (the tendency of an entity to find a particular trajectory from varying starting points). While FT offers a nuanced analysis of field relationships, it describes too many physical processes as teleological. Emblematic of it is that it pays no attention to the difference between two types of asymmetric change: the linear processes governed by global thermodynamic tendencies, which I call “terminal” because their end is increasing entropy, and the processes that utilize these same tendencies to stay away from equilibrium by creating local deviations of the second law, which I call “targeted”. Living systems use terminal field effects to prevent thermodynamic degradation and promote their own forms of organization. They generate their sources of guidance and are not just targeted with respect to external fields but also to themselves. Since the artifactual model of FT does not seem able to account for targeted tendencies, adopting the distinction between terminal and targeted processes could help FT overcome some of the perceived limits of its deflationary stance.