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How to Categorise States | Condition, Stability, Duration, Transition, Observability and Recovery

A state is a condition of an entity or system at a particular time.

Open, closed, active, dormant, healthy, overloaded, approved, failed, charged, empty, published and under review are all states. They do not tell us what a thing is; they tell us what condition it is currently in.

Quick answer: how should states be categorised?

  • Condition: what is true now?
  • Stability: stable, unstable, transient, oscillating?
  • Duration: momentary, temporary, persistent?
  • Observability: directly observed or inferred?
  • Transition: what states can come before or after?
  • Reversibility: can the state be left or restored?
  • Validity: is the state allowed, degraded, failed or exceptional?
  • Context: under which operating mode does it apply?
  • Uncertainty: how certain is the state assignment?
  • Recovery: what action can restore an acceptable state?

This article applies How to Categorise Anything to stateful systems and entities.

1. Separate state from identity

A broken chair is still a chair. Broken is state; chair is type.

2. Separate state from event

An event changes state. “Door opened” is an event; “door open” is a state.

3. Separate state from process

A process can move an entity through many states.

4. State should be time-stamped

A state assignment without time can become misleading as the underlying entity changes.

5. Binary states are simple but limited

On/off, open/closed and valid/invalid are useful when the domain genuinely has two discrete conditions.

6. Multi-state systems preserve more detail

Draft, review, approved, published and superseded describe more than a published/not-published binary.

7. Continuous states may need ranges

Temperature, pressure, charge and utilisation can vary continuously before thresholds create discrete labels.

8. Threshold states are administrative abstractions

Low, normal and high compress a continuous variable into operational categories.

9. Stable states persist

Small disturbances do not immediately move the system elsewhere.

10. Unstable states amplify disturbance

Small changes can push the system rapidly into another condition.

11. Transient states are brief

Starting, switching, calibrating and handshaking can exist only during transition.

12. Persistent states deserve different handling

A momentary overload differs from a sustained overload that threatens system integrity.

13. Oscillating states form patterns

Repeated movement among states may indicate feedback, instability or normal cyclic behaviour.

14. Observed states differ from inferred states

A visible indicator may directly show one state; hidden internal state may be estimated from several signals.

15. Inferred states need confidence

Healthy, failing, compromised and ready may be probabilistic conclusions rather than directly measured facts.

16. State machines define allowed transitions

Not every state can move directly into every other state.

17. Transition rules matter

A draft may move to review, but a deleted record may require restoration before editing.

18. Illegal states should be explicit

Some combinations of properties should never occur and can signal data corruption or process failure.

19. Degraded states preserve partial function

A system can remain operational while losing speed, redundancy or quality.

20. Failed states lose required function

Failure should be defined against required capability rather than appearance alone.

21. Safe states protect containment

Emergency systems may transition deliberately into reduced-function but lower-risk modes.

22. Recovery states deserve classification

Restarting, restoring, synchronising and validating can be distinct from normal operation.

23. Reversible states permit return

Paused can return to active; draft can return from review to editing.

24. Irreversible states change history

Some legal, physical or destructive transitions cannot be restored exactly.

25. State and status can differ

Status often describes workflow or administrative interpretation layered over underlying condition.

26. Context changes valid states

A system in maintenance mode can legitimately occupy states that would count as failure during production.

27. Multiple state dimensions can coexist

A server can be operational, overloaded, geographically active and security-restricted at the same time.

28. Facets prevent state explosion

Represent power, health, access and workflow state separately rather than creating every combination as a unique label.

29. State duration matters for alerts

A state that persists beyond a threshold may trigger escalation even if brief occurrences are normal.

30. State changes should preserve cause

Record whether transition was caused by user action, automatic rule, event, failure or external dependency.

31. State histories enable reconstruction

Sequences of states and transitions can reveal where a process or system began to fail.

32. State drift can reveal new modes

Repeated observations outside known states may indicate that the state model is incomplete.

33. AI can infer hidden states

Models can combine signals to estimate condition, but inferred states should preserve confidence and evidence.

34. State inference can be biased

If training data underrepresent rare or degraded states, models may over-predict normal conditions.

35. State taxonomies need versioning

New operating modes and failure conditions can require new states or revised transition rules.

36. State categories should connect to actions

Useful states determine monitoring, routing, maintenance, escalation or recovery behaviour.

37. A practical state record

  • entity ID;
  • state dimension;
  • state value;
  • start time;
  • end time;
  • stability;
  • observed or inferred;
  • evidence;
  • confidence;
  • preceding state;
  • transition cause;
  • allowed next states;
  • reversibility;
  • recovery action;
  • state-model version.

38. State categories should improve control

A useful state model changes what the system or operator should do next.

39. States make change legible

They provide snapshots from which transitions, trends and histories can be reconstructed.

40. The deeper idea

Identity tells us what something is. State tells us what condition that thing occupies now.

To categorise a state well is to preserve condition, time, evidence, transition and recovery without confusing temporary circumstance with permanent identity.

Final answer

Categorise states by condition, stability, duration, observability, transition, reversibility, validity, context, uncertainty and recovery. Separate state from identity, event and process, use multiple state dimensions where necessary, and preserve state history so system change remains explainable.

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