Language and the Differentiation of Possibility: 3 Register, Situation Type, and the Semiotic Shaping of Possibility

If grammar provides the architecture of possibility, register specifies its operating range.

In Halliday’s theory, register is not a contextual layer, nor a textual category, nor a classificatory label. It is a semantic subpotential of language — a patterned region of the semantic system that is selectively activated in relation to a type of situation.

Understanding this properly is essential if we are to grasp how language shapes possibility without invoking interiors, intentions, or representations.

Register as Semantic Subpotential

Language, as a system, contains vast potential. Not all of that potential is active at once.

A register is a constrained semantic subpotential: a region of the semantic system that becomes salient because it is functional for coordinating action in a particular type of situation.

Register does not describe situations.

Register realises situation types.

This directionality matters.

Situation Type as Contextual Subpotential

A situation type is not an event, and it is not a text. It is a contextual subpotential — a recurrent configuration of field, tenor, and mode within culture.

Situation types define:

• what kinds of activity are relevant (field)

• what relations among participants are at stake (tenor)

• what role language plays in coordination (mode)

They are potentials, not instances.

A lecture, a legal hearing, a lab report, a casual conversation — these are not texts yet. They are types of situations that make certain semiotic resources functional.

Realisation, Not Reflection

The relation between register and situation type is one of realisation, not representation.

• Situation type (contextual subpotential)
  ↓ realised by

• Register (semantic subpotential)
  ↓ realised by

• Lexicogrammar
  ↓ instantiated as

• Text in situation

At no point does language “mirror” context. Nor does context determine wording directly. Instead, each stratum constrains and enables the one below it, shaping the field of possibility.

Instantiation and the Event of Meaning

Texts are not systems. They are instances.

A text instantiates:

• a particular selection within a register

• which itself instantiates a portion of the semantic system

• which realises a situation type

• within a broader cultural system

This is why meaning is neither private nor abstract. Meaning happens as an event of instantiation, where potential becomes actual under constraint.

Why This Matters for Possibility

From a relational ontology perspective, this architecture explains how language shapes possibility without invoking inner states.

Register:

• does not encode intentions

• does not carry meanings inside it

• does not represent situations

Instead, it structures what distinctions are available, what actions are intelligible, and what trajectories of coordination can stabilise.

Different registers make different futures possible — not by persuasion, but by functional affordance.

Knowledge, Power, and Register

Because registers stabilise ways of meaning in relation to situation types, they are central to the formation of knowledge and power.

Scientific registers make certain kinds of explanation possible. Legal registers make certain kinds of obligation actionable. Bureaucratic registers make certain forms of accountability enforceable.

These are not ideological effects first. They are semiotic effects, grounded in the selective activation of semantic potential.

No Genre, No Interiors

Nothing here requires a theory of genre as an additional stratum, nor an appeal to speaker intention or mental representation.

The explanatory work is done by:

• stratification

• instantiation

• realisation

• constrained semantic potential

This is Halliday’s architecture doing exactly what it was designed to do.

Looking Ahead

With register and situation type now firmly in place, we are ready to explore how semiotic systems reconfigure themselves, opening new possibilities through recombination.

The next post will therefore be:

Metaphor, Recombination, and Semiotic Novelty

— where creativity returns, not as imagination in the head, but as patterned reorganisation within the semantic system itself.