The Problem of Placeholder Concepts in Biology

Biological explanation frequently relies on a set of concepts that appear to carry explanatory weight but whose meaning remains under-specified. Terms such as emergence, information, design, and cognition are widely used across biology and related disciplines to describe complex organisation, adaptive behaviour, and system-wide coordination. They capture something real about living systems. Yet their explanatory status is often unclear.

In many contexts, these terms function as explanatory placeholders. They are invoked to mark the presence of organised complexity without specifying the organisational conditions that produce and sustain it. To say that a system is emergent, that it processes information, or that its behaviour is cognitive can indicate that something significant is occurring, but it does not by itself explain how or why that organisation exists.

This is not a failure of the concepts themselves. Each arises from attempts to describe genuine features of biological systems: the formation of extended organisation across scale, the sensitivity of systems to their environment, the coordination of activity, and the purposive character of living processes. The difficulty lies in how these terms are used. When treated as explanatory primitives, they obscure the organisational basis of the phenomena they describe.

The Agency–Process–Scale (APS) framework addresses this problem by clarifying the structure of biological explanation. Rather than rejecting these concepts, APS situates them within a more precise account of how living systems are organised. What is often described in terms of emergence, information, design, or cognition can be understood more explicitly in terms of viability-oriented, constraint-closed organisation, in which activity is structured, stabilised, and transformed across time and scale.

For a formal account of how biological explanation is structured, see [The Explanatory Geometry of Biology — How APS Organises Biological Explanation]. That article specifies the conditions under which biological explanation is possible. The present article addresses a complementary task. It examines how widely used concepts function within biological explanation and shows how they can be clarified by grounding them in the organisational framework specified by APS.

Why Placeholder Concepts Persist

The persistence of placeholder concepts in biology reflects the genuine complexity of living systems. Biological organisation is distributed across scale, dynamically maintained, and historically transformed. Extended patterns of organisation are formed and stabilised across scale in ways that are not immediately evident from local interactions. Systems exhibit sensitivity, coordination, and adaptability that resist simple description.

In this context, terms such as emergence, information, and cognition serve an important descriptive role. They provide a way of marking phenomena that are difficult to characterise in purely component-based or mechanistic descriptions. They allow scientists to refer to system-wide organisation, functional integration, and adaptive behaviour without specifying the full underlying structure.

However, this descriptive utility comes at a cost. When such terms are used without clarification, they obscure the distinction between description and explanation. A phenomenon may be labelled as emergent or informational without identifying the processes and relations through which it is produced and maintained. The concept then functions as a placeholder, signalling that something requires explanation while simultaneously deferring that explanation.

This dual role—descriptive clarity combined with explanatory ambiguity—explains both the usefulness and the limitations of these terms. They persist because they capture real features of biological systems, but they remain problematic because they are often treated as if they themselves provide explanation.

Biology has long sought to naturalise concepts such as function, purpose, information, and cognition—that is, to explain them without appealing to intention, design, representation, or irreducible teleology. Different traditions have addressed this task in different ways: selected-effects accounts ground function in evolutionary history, causal role accounts in system contribution, teleonomy in the effects of natural selection, information theory in signalling and coding, and enactive approaches in organisation and sense-making. These approaches capture important aspects of biological systems, but they tend to address each concept in isolation. APS takes a different approach. Rather than offering separate naturalisations, it shows that these concepts can be understood as expressions of a single underlying mode of organisation: viability-oriented, constraint-closed activity. What appear as distinct explanatory problems are thus unified within a common framework.

This does not replace existing insights, but repositions them within a more explicit account of how biological organisation is produced, maintained, and transformed.

For example, what is described as the function of the heart, the informational sensitivity of a cell, or the cognitive behaviour of an organism can all be understood as different expressions of the same underlying organisation: the evaluation, structuring, and coordination of activity in relation to conditions that sustain viability.

The APS Strategy: Clarification Without Elimination

APS does not eliminate placeholder concepts. Instead, it clarifies their role.

The central move is to distinguish between descriptive and explanatory uses. Concepts such as emergence, information, design, and cognition may be retained as descriptive shorthand, but they are not treated as explanatory primitives. Explanation is instead grounded in the organisation of living systems: in how activity is structured, how constraints are maintained, and how systems sustain their own persistence.

In APS, living systems are viability-oriented, constraint-closed organisations. They maintain the conditions of their own existence through ongoing activity. This activity is normatively structured: some processes support persistence, while others undermine it. This asymmetry is enacted through evaluation, the differential modulation of activity in relation to viability.

Within this framework, semiosis structures differences as mattering for the system, and cognition arises when evaluative activity becomes sufficiently integrated and temporally extended across time. Biological design refers to the structured organisation of activity through which systems sustain themselves, while what is often described as emergence corresponds to the reorganisation of constraint-closed systems across scale and time.

These concepts are thus not rejected, but re-specified. Their descriptive role is preserved, but their explanatory content is located within a unified account of biological organisation.

Case Studies in Re-Specification

The value of this approach can be seen by examining how several commonly used concepts are clarified within APS.

Emergence is often used to describe the formation of extended organisation. In APS, this is understood as the continuous production and transformation of constraint-closed systems. There is no need to invoke irreducible novelty; properties of organised systems reflect reconfigured constraint relations across scale.

Information is frequently treated as a fundamental feature of biological systems. APS reverses this perspective. Information is not primary, but derivative of organisation. Differences become informative only insofar as they matter for the viability of the system, which is determined through evaluation and semiosis.

Cognition is often taken as a defining feature of life or as a specialised property of complex organisms. APS situates it more precisely. All living systems exhibit evaluation, but cognition arises only when this evaluative activity becomes sufficiently integrated and temporally extended. It is a development within biological organisation, not its foundation.

Design is commonly interpreted either as the result of external intention or as an illusion produced by evolutionary processes. APS shows that biological design is real, but not imposed. It is the structured organisation of activity through which living systems sustain themselves.

In each case, the concept captures something real. The difficulty lies in its use as an explanatory endpoint. APS replaces this with an account of how the relevant organisation is produced and maintained.

What Replaces Placeholder Concepts

By clarifying these concepts, APS does not leave an explanatory gap. It replaces placeholder terms with an explicit organisational framework.

Biological explanation proceeds through the analysis of:

  • viability-oriented organisation
  • constraint closure
  • evaluation and the modulation of activity
  • semiosis and the structuring of meaningful differences
  • coordination across scale and time

Within this framework, system-wide phenomena are not explained by invoking abstract categories, but by identifying the processes and relations that generate them. What is described as emergence, information, or cognition is understood as the outcome of these organisational dynamics viewed at a particular resolution.

This shift does not reduce complexity. It makes it tractable. By grounding explanation in organisation, APS provides a way of analysing biological systems that remains continuous across scale and sensitive to the conditions that sustain them.

Implications for Biological Explanation

The replacement of placeholder concepts with explicit organisational accounts has important implications.

First, it removes explanatory ambiguity. Terms that previously functioned as shorthand are given precise meaning within a broader framework.

Second, it preserves continuity across biological domains. The same principles apply to cellular processes, organismal regulation, cognition, and ecological organisation.

Third, it avoids both reductionism and metaphysical inflation. Biological phenomena are neither reduced to isolated components nor treated as irreducible mysteries. They are understood as organised processes that can be analysed in terms of their structure and dynamics.

Finally, it reorients the task of explanation. Instead of asking whether a phenomenon is emergent, informational, or cognitive, the question becomes how it is organised, how it is maintained, and how it contributes to the persistence of the system.

Conclusion

Concepts such as emergence, information, design, and cognition have long played a central role in biological thought. They capture real features of living systems, but they often function as explanatory placeholders when their meaning is left unspecified.

APS retains their descriptive usefulness while removing their explanatory ambiguity. Biological phenomena are not explained by invoking these concepts, but by analysing the viability-oriented, constraint-closed organisation that makes them possible.

In this way, APS replaces loosely defined abstractions with a unified account of organised biological activity. What were once treated as explanatory endpoints become phenomena to be explained in terms of organisation, process, and scale.

Seen in this light, phenomena often described as emergent, informational, functional, or cognitive do not require distinct explanatory frameworks. The coordinated activity of a heart, the sensitivity of a cell to its environment, and the adaptive behaviour of an organism can all be understood as expressions of the same underlying organisation: the evaluation, structuring, and coordination of activity in relation to conditions that sustain viability. What differ are not the principles involved, but the ways in which this organisation is stabilised, integrated, and extended across scale and time.

Key Point

APS replaces explanatory placeholder concepts with explicit organisational accounts: emergence, information, design, and cognition are not primitives, but expressions of viability-oriented, constraint-closed biological organisation.