Why APS? Why Biology Still Needs an Organisational Framework for Life

Where This Article Fits Having introduced APS in What is APS?, this article explains why such a framework is needed. It identifies the unresolved explanatory problems that motivate APS, argues that contemporary biology still lacks an adequate account of the organising activity characteristic of living systems, and shows how APS seeks to address that gap. Readers may wish to read this article immediately after What Is APS? before continuing to the broader orientation pathway.

Section 1 — Introduction. Biology’s Extraordinary Achievement

Modern biology has transformed our understanding of life more profoundly than perhaps any previous scientific discipline. Yet the continuing success of biology has revealed an unexpected consequence: the better we understand living systems, the more clearly we can ask what kind of phenomenon life actually is.

Over little more than a century and a half, biology has revealed the mechanisms of heredity, the dynamics of evolution, the organisation of cells, the molecular basis of development, the complexity of ecological interactions, and the biochemical processes that sustain life. Few scientific disciplines have reshaped both human knowledge and practical life so profoundly.

This achievement has been cumulative rather than dependent upon a single revolutionary discovery. Darwin’s theory of evolution by natural selection unified the diversity of life within a common historical framework. Genetics explained the inheritance of biological traits. Molecular biology uncovered the physical basis of genetic information and cellular function. Physiology, developmental biology, ecology, and systems biology each expanded biology’s explanatory reach by revealing new dimensions of living organisation. Together, these fields have produced an extraordinarily rich understanding of how living systems function, develop, reproduce, adapt, and evolve.

The practical consequences have been equally remarkable. Modern biology underpins contemporary medicine, agriculture, biotechnology, conservation, and public health. It informs responses to infectious disease, guides ecosystem management, enables genetic diagnosis and therapy, and contributes to understanding global environmental change. The explanatory power of biology is therefore measured not only by its theoretical achievements but also by its capacity to improve human life and deepen our understanding of the living world.

Importantly, this success has never depended upon a single explanatory tradition. Biological knowledge has advanced through the interaction of multiple complementary approaches. Mechanistic explanations identify how biological phenomena occur. Evolutionary explanations account for their historical transformation. Developmental biology explains the emergence of organismal form and function throughout the life cycle. Ecology situates organisms within wider environmental relationships. Systems biology investigates the coordinated interactions through which complex biological behaviour emerges. Each perspective illuminates aspects of living systems that cannot be fully understood in isolation from the others. As biology has expanded, its explanatory traditions have become increasingly complementary rather than mutually exclusive, creating opportunities for integrative organisational frameworks alongside continued empirical investigation.

Recognising this diversity is essential. APS does not begin from the claim that modern biology has failed or that its established explanatory traditions are inadequate. On the contrary, the continuing success of modern biology provides the very foundation upon which further conceptual work becomes possible. Mature sciences often discover that their greatest achievements reveal new kinds of foundational questions. Biology is no exception.

Indeed, the history of science suggests that intellectually mature disciplines periodically return to questions lying beneath their expanding body of empirical knowledge. Progress in observation, experimentation, and theory frequently reveals new conceptual issues rather than eliminating them. Physics continues to investigate the foundations of space, time, and quantum reality despite its extraordinary predictive success. Likewise, biology continues to ask what distinguishes living systems, what constitutes biological organisation, and what kinds of explanation are required to understand life as a distinctive natural phenomenon. Such questions do not diminish the achievements of biological science; they arise precisely because those achievements have made deeper forms of understanding possible.

It is within this context that the Agency–Process–Scale (APS) framework should be understood. APS was not developed in opposition to modern biology, nor as a replacement for its established theories. It emerged from the recognition that the continuing success of biological research has brought foundational questions concerning living organisation into increasingly sharp focus. Before considering how APS approaches those questions, it is therefore necessary to understand why successful sciences continue to revisit their conceptual foundations.

Section 2 — Why Success Does Not End Inquiry

Modern biology’s extraordinary achievements do not bring biological inquiry to an end. On the contrary, they make new kinds of questions possible. As knowledge accumulates, sciences often discover that progress reveals deeper conceptual issues rather than eliminating them. The history of science repeatedly shows that explanatory success and foundational inquiry develop together.

This pattern is familiar across the natural sciences. Physics has achieved remarkable predictive power while continuing to investigate the nature of space, time, gravity, and quantum reality. Chemistry successfully explains the composition and transformation of matter while still examining the conceptual foundations of chemical organisation and emergence. Mature sciences do not cease asking fundamental questions because they have become successful; they ask them because success has clarified what remains to be understood.

Biology occupies a similar position. During the past century, enormous advances have illuminated the mechanisms through which living systems develop, reproduce, adapt, communicate, regulate, and evolve. These achievements have transformed our understanding of life at every level of investigation. Yet they have also sharpened several enduring questions. What distinguishes living systems from other organised physical systems? What makes biological organisation a distinctive object of scientific explanation? What, ultimately, is biology attempting to explain?

These questions are sometimes misunderstood as attempts to replace empirical biology with abstract speculation. In fact, they arise from the opposite impulse. The more completely biological mechanisms become understood, the more clearly one can ask what those mechanisms collectively achieve as aspects of living organisation. The issue is not whether molecular biology, physiology, ecology, or evolutionary theory are successful—they demonstrably are—but whether their combined achievements point towards a broader organisational target that deserves explicit investigation.

This distinction is important because it concerns the nature of explanation rather than the accumulation of evidence. Scientific disciplines routinely distinguish between explaining individual phenomena and clarifying the conceptual framework within which those explanations acquire their coherence. Biology explains countless biological processes with extraordinary precision. A different, though complementary, question asks how those diverse explanations relate to one another as explanations of living systems.

For this reason, foundational questions should not be interpreted as signs of disciplinary weakness. They are characteristic of intellectually mature sciences. Every successful explanatory framework eventually raises questions about its own organising concepts, assumptions, and scope. In biology, questions concerning life, organisation, individuality, function, agency, information, and explanation itself remain active precisely because they concern the conceptual organisation of biological knowledge rather than unresolved empirical observations.

Theoretical biology and the philosophy of biology have long recognised the importance of these questions. They investigate not only particular biological phenomena but also the conceptual structures through which biology understands its subject matter. Their aim is not to compete with experimental biology but to clarify the explanatory architecture that allows diverse biological discoveries to form a coherent scientific understanding of life. Within these fields, discussions of organisation, autonomy, mechanism, function, emergence, and individuality reflect an ongoing effort to understand what kinds of explanation are appropriate for living systems.

It is within this continuing conversation that APS should be situated. The framework did not arise because biology lacked evidence, nor because existing theories had ceased to be productive. Rather, it emerged from the recognition that biology’s continuing success has made questions about the organisation of living systems increasingly explicit. Before introducing APS itself, however, one further step is required. We must identify more precisely the nature of the explanatory challenge that these questions reveal.

Section 3 — The Organisational Target of Biological Explanation

The continuing success of modern biology raises a question that is easily overlooked. If biology can already explain heredity, development, metabolism, physiology, behaviour, adaptation, and evolution with remarkable precision, what remains to be explained? At first sight, the answer might appear to be simply “more biology”—more mechanisms, more genes, more pathways, and more interactions. Yet many of the continuing discussions within theoretical biology suggest that the remaining challenge is of a different kind. It concerns not merely the accumulation of additional knowledge, but the clarification of what biological explanation is ultimately attempting to explain.

Every biological discipline investigates some aspect of living systems. Molecular biology explains cellular processes through molecular interactions. Physiology explains the coordinated functioning of organisms. Evolutionary biology explains the historical transformation of populations. Developmental biology explains the emergence and maintenance of organised form throughout the life cycle. Ecology explains the relationships between organisms and their environments. Each contributes indispensable knowledge. Their explanatory success is beyond question.

What is striking, however, is that these explanations are not isolated from one another. They are recognised as biological explanations because they investigate living systems from different, yet complementary, perspectives. This raises a deeper question: what gives these diverse explanations their common scientific target? What makes them collectively explanations of life?

This question does not ask biology to abandon mechanisms in favour of some alternative form of explanation. Mechanistic explanation remains indispensable because living systems are materially realised through physical and chemical processes. Nor does it seek a single master theory capable of replacing evolutionary, developmental, physiological, or ecological explanation. The strength of biology lies precisely in the diversity of its complementary explanatory traditions.

The issue instead concerns the relationship between those traditions. Biological mechanisms explain how particular processes occur. Evolution explains how those processes have been historically transformed. Development explains how organised form emerges and changes throughout an organism’s life. Ecology explains how living systems exist within wider environmental relationships. Together these perspectives illuminate different aspects of the same scientific subject. The remaining challenge is therefore not to choose between them, but to understand what they are jointly explaining.

For this reason, many developments within theoretical biology have increasingly turned towards organisation as an object of explanation in its own right. General systems theory emphasised organised wholes rather than isolated components. Relational biology investigated organisational dependencies that cannot be reduced to individual parts. Autopoietic theory explored the self-producing organisation characteristic of living systems. More recent work on biological autonomy, organisational closure, constraint-based organisation, and organisational approaches to function has continued this broader effort to understand how living systems maintain themselves as coherent entities. Although these traditions differ substantially in their concepts and conclusions, they share the recognition that organisation is not merely a convenient description but an indispensable target of biological explanation.

This development should not be interpreted as a departure from empirical biology. Rather, it reflects the continuing maturation of biological science itself. As empirical knowledge has expanded, questions concerning the organisation of that knowledge have become increasingly explicit. Mature sciences routinely progress from explaining individual phenomena to clarifying the conceptual structures that unify those explanations. Biology has reached precisely such a stage. The question is no longer simply how particular biological processes occur, but what kind of organisational framework best captures the distinctive character of living systems that those processes collectively constitute.

Seen in this light, the continuing discussions surrounding organisation, individuality, function, autonomy, agency, and biological explanation are not isolated debates. They represent different attempts to identify the organisational target that unifies biological inquiry. They ask, in different ways, what it is about living systems that makes them distinctive objects of scientific explanation.

The Agency–Process–Scale framework enters this conversation at precisely this point. APS begins from the proposal that biology’s central explanatory task is not exhausted by describing mechanisms or reconstructing evolutionary histories, important though those remain. It asks whether the organised persistence of living systems provides the organisational target that unifies biology’s diverse explanatory traditions.

Rather than replacing biology’s established sciences, APS seeks to clarify the organisational perspective within which their complementary achievements can be understood as investigations of one and the same living phenomenon.

Modern Biology
        │
        ▼
Continuing Explanatory Success
        │
        ▼
Increasingly Explicit
Foundational Questions
        │
        ▼
Organisation as the
Target of Explanation
        │
        ▼
Agency–Process–Scale

Organisation Is Not an Alternative to Biology

APS does not argue that biological mechanisms, evolutionary history, development, or ecology are insufficient. It argues that their combined explanatory success makes it increasingly possible—and increasingly necessary—to ask what kind of organised phenomenon those complementary explanations collectively investigate.

Section 4 — Why APS Was Developed

The Agency–Process–Scale (APS) framework was developed in response to the explanatory question identified in the preceding section. It does not begin by proposing a new biological mechanism, a new evolutionary theory, or a new account of molecular function. Instead, it begins by asking whether biology can more clearly identify the organisational target that unifies its diverse explanatory traditions.

APS therefore begins from a methodological rather than a mechanistic proposal. It asks whether living systems are best understood as a distinctive form of viability-oriented, constraint-closed organisation whose continuing activity maintains and re-establishes the conditions of its own persistence. On this view, the diverse processes investigated throughout biology are not isolated phenomena but different expressions of a single organised reality.

This perspective distinguishes two complementary tasks within biological explanation. The first is to explain particular biological phenomena through the appropriate empirical sciences, including molecular biology, physiology, developmental biology, ecology, and evolutionary biology. The second is to clarify the organisational framework within which those explanations become explanations of living systems. APS addresses this second task. It therefore complements, rather than competes with, the established biological sciences.

This orientation also explains why APS is organised around three complementary analytical projections:

Agency, Process, and Scale. These are neither separate components of reality nor independent causal forces. They are complementary analytical perspectives on one and the same living organisation.

Agency asks what living systems do. It investigates the viability-oriented activity through which organisms maintain and re-establish the conditions of their own persistence.

Process asks how that organisation is continuously maintained despite ongoing material turnover, developmental change, and environmental variation. It examines the dynamic continuity through which organised persistence is sustained.

Scale asks where that organisation is realised across spatial and temporal extents. It investigates how organised persistence is expressed across interacting domains without treating those domains as explanatory hierarchies.

Taken together, these analytical projections provide a common organisational framework for investigating living systems while preserving the specialised explanatory methods of biology. Evolutionary theory continues to explain historical transformation. Molecular biology continues to investigate biochemical mechanisms. Ecology continues to explain organism–environment relationships. APS instead asks how these complementary explanations contribute to understanding life as viability-oriented, constraint-closed organisation.

The framework therefore makes a deliberately modest claim. It does not propose that Agency, Process, and Scale answer every biological question. Rather, it proposes that they provide a coherent organisational framework for investigating a particular class of questions concerning living organisation. APS should therefore be understood not primarily as a new biological theory, but as a research programme concerned with clarifying the conceptual organisation of biological explanation itself.

Seen in this way, APS belongs within the continuing development of theoretical biology. It emerges from biology’s existing achievements, engages with long-standing questions concerning organisation and explanation, and seeks to provide a systematic framework through which those questions can be investigated further. Its purpose is not to replace biology’s established explanatory traditions, but to clarify how their complementary insights contribute to a unified understanding of life.

Section 5 — What APS Proposes

The preceding sections have argued that the continuing success of modern biology has made questions concerning the organisation of living systems increasingly explicit. APS responds to those questions by proposing an organisational framework through which biological explanation can investigate the persistence of living systems without replacing the established explanatory achievements of contemporary biology.

The central proposal of APS is straightforward. Living systems are understood as viability-oriented, constraint-closed organisation. Life is not identified with a particular molecule, structure, process, or historical event. Rather, it consists in the ongoing organisation through which living systems actively maintain and re-establish the conditions of their own persistence. This proposal does not compete with molecular, physiological, developmental, ecological, or evolutionary explanations. Instead, it provides the organisational perspective within which those complementary explanations can be understood as investigations of the same living phenomenon.

To investigate this organisation systematically, APS employs three complementary analytical projections: Agency, Process, and Scale.

Agency asks what living systems do. It investigates the viability-oriented activity through which organisms maintain and re-establish the conditions of their own persistence.

Process asks how that activity is continuously organised despite material turnover, developmental change, and environmental variation. It investigates the continuity through which organised persistence is maintained.

Scale asks where organised persistence is realised across spatial and temporal extents. It investigates how living organisation is expressed across interacting domains without treating those domains as explanatory hierarchies.

These analytical projections do not divide living systems into separate components, nor do they represent independent causal forces. They are complementary analytical perspectives on one and the same living organisation. Each addresses questions that the others cannot fully answer alone, yet each depends upon the others for a coherent understanding of living systems.

From this common foundation, APS develops a wider conceptual architecture. Questions concerning biological evaluation, significance, cognition, individuality, development, evolution, social organisation, morality, and biological explanation are investigated as successive elaborations of viability-oriented organisation rather than as isolated theoretical domains. In this way, APS seeks to develop a coherent organisational framework within which the diversity of biological inquiry can be understood without reducing one explanatory tradition to another.

APS should therefore not be regarded as a single hypothesis awaiting confirmation or refutation. It is more appropriately understood as a research programme that organises questions, clarifies conceptual relationships, and identifies explanatory priorities. Individual biological disciplines continue to investigate their own specialised phenomena and mechanisms. APS asks how those diverse investigations contribute to a unified understanding of life as a distinctive natural phenomenon.

The remainder of the APS corpus develops these ideas in detail. Dedicated articles examine the nature of life, biological agency, organised persistence, constraint closure, process, scale, biological evaluation, cognition, individuality, morality, and biological explanation. Each explores one aspect of the wider organisational framework. Together they seek to provide an increasingly integrated account of living organisation while remaining firmly grounded in the continuing empirical achievements of modern biology.

Concluding Reflection

Modern biology continues to expand our understanding of living systems through increasingly sophisticated empirical investigation. At the same time, its continuing success has made questions concerning the organisation of life progressively more explicit. APS represents one attempt to investigate those questions through a unified organisational framework centred on viability-oriented, constraint-closed organisation.

Whether that framework ultimately proves scientifically valuable will depend upon its capacity to illuminate biological phenomena, clarify conceptual relationships, stimulate productive research, and contribute to the continuing development of theoretical biology. Those questions can only be answered through ongoing scientific and philosophical engagement.

The purpose of this article has therefore not been to establish every aspect of the APS framework. Rather, it has been to explain why the continuing development of modern biology provides compelling reasons to investigate such a framework and why questions concerning living organisation remain central to the future of biological explanation.