Review | Origins of Biological Teleology: How Constraints Represent Ends

Introduction

In 1943 Arturo Rosenblueth, Norbert Wiener, and Julian Bigelow, three prominent cyberneticians, published a paper entitled Behavior, Purpose and Teleology, a masterpiece which laid the groundwork for understanding teleology in terms of control systems and feedback mechanisms. They introduced a classification of behavior, distinguishing between purposeless and purposeful activity, with the latter being characterized by goal-directed processes. Their work emphasized the importance of negative feedback as a mechanism for achieving a stable equilibrium, laying the foundation for cybernetics and influencing subsequent debates on biological organization.

By shifting the focus from intrinsic teleological properties to relational dynamics, they provided a framework that resonates with modern discussions of constraints in biological systems. Throughout the history of biology and philosophy, the concept of teleology—explaining biological phenomena in terms of purpose or ends—has been met with skepticism and revision. Teleological explanations, often accused of implying backward causation, were largely abandoned in favor of mechanistic and externalist paradigms. However, the persistence of teleological notions in biology suggests that an entirely eliminative approach is insufficient.

Today I am going to review the paper Origins of Biological Teleology: How Constraints Represent Ends by Miguel García-Valdecasas and Terrence W. Deacon, which provides a framework to naturalize teleological causality through the concept of constraints, particularly in the context of the molecular process termed autogenesis. I am grateful to Gonçalo Braga Fibra, who sent me this and other interesting references on the subject.

Teleology and its taxonomy

The article outlines five alternative dichotomies that characterize teleological causality:

1. Internalist vs. Externalist – Traditional internalist views, like Aristotle’s, see purpose as inherent to an organism, whereas externalist views (e.g., Darwinian selection) explain teleology as externally imposed. The article proposes an approach that integrates aspects of both.
2. Constitutive vs. Descriptive – While descriptive accounts (e.g., teleonomy) explain purpose as a byproduct of natural selection, a constitutive approach demands an intrinsic causal mechanism for teleology. The authors endorse a constitutive perspective.
3. Targeted vs. Terminal – Terminal processes reach a natural stopping point (e.g., thermodynamic equilibrium), whereas targeted processes require active maintenance of a far-from-equilibrium state, characteristic of life.
4. Normative vs. Nonnormative – Living systems must actively maintain their state, giving rise to normativity in biological processes.
5. General vs. Particular – Biological ends are best understood in terms of general constraints rather than fixed, particular outcomes.

This taxonomy provides a systematic way to assess different theories of teleology and serves as a foundation for the rest of the paper.

Constraints as relational properties

Constraints are fundamental to biological organization. Unlike traditional views that attempt to encode constraints as structures or processes, the article argues that constraints should be understood relationally. They define form and order without referring to ideal types. A more constrained system exhibits reduced dynamic variability, meaning that organized processes impose limitations on their own potential changes. This perspective is crucial in distinguishing biological organization from mere physical or chemical processes, as constraints shape the emergence and persistence of living systems.

Among biological constraints, hologenic constraints play a critical role in maintaining systemic unity. A hologenic constraint is a higher-order relational constraint that ensures the co-dependence of multiple self-organizing processes, preventing them from reaching thermodynamic equilibrium and disintegration. By maintaining the integrity of an individuated system, hologenic constraints allow for continuity and reconstitution, ensuring the persistence of autogenic processes despite external perturbations.

Autogenesis and Representation

Autogenesis provides an empirical model demonstrating minimal teleological causality. It emerges from the reciprocal dependence of two self-organizing processes:

1. Reciprocal Catalysis – A set of catalytic reactions that mutually enhance each other’s persistence.
2. Self-Assembly – The spontaneous organization of molecular structures, such as capsids in viruses.

A key feature of autogenesis is co-locality, ensuring that reciprocal catalysis and self-assembly remain mutually supportive. According to the authors, this synergy gives rise to the hologenic constraints mentioned above. On the other hand, the paper argues that the simplest form of representation is an affordance, a property of a system that allows it to map external conditions to internal constraints. Three core properties define this biological representation:

1. Normativity – The system actively maintains itself.
2. Memory – The system preserves its organizational form across cycles of change.
3. Discrimination – The system differentiates between active and inert states, responding accordingly.

These properties establish a foundational link between biological teleology and representation, without requiring mentalistic explanations. Now, why autogenesis? At the end of their paper, the authors mentioned other three classes of explanation for biological teleology:

• Replication-Based Theories (e.g., RNA World) focus on molecular replication but lack a framework for intrinsic normativity.
• Self-Organization-Based Theories emphasize spontaneous order formation but do not account for the individuated persistence characteristic of life.
• Autonomy-Based Theories (e.g., autopoiesis) stress systemic closure but often neglect the fundamental role of constraints in teleological causality.

In this way, following a holistic approach, autogenesis integrates elements of these approaches while emphasizing the critical role of constraints in maintaining system integrity and naturalizing teleology.

Conclusion

Autogenesis exemplifies an external, constitutive, targeted-directed, normative, and general form of teleology. By framing teleological causality in terms of constraints, rather than structures or processes, the model avoids idealistic pitfalls while grounding biological purpose in physical principles. This perspective bridges the gap between mechanistic explanations and the undeniable role of purposive behavior in living systems, offering a robust foundation for a naturalized theory of biological teleology.

However, some aspects of the framework remain open to further exploration. For instance, while hologenic constraints provide a mechanism for systemic unity, it is still unclear how these constraints interact with external perturbations over extended evolutionary timescales. Additionally, the precise relationship between autogenic processes and higher-order biological functions, such as metabolic pathways and neural representations, requires deeper empirical investigation. Further research could clarify how autogenesis scales up to complex organisms and whether similar constraint-driven mechanisms underlie more advanced forms of teleological causality.