---
key: mechanic/detective--family-22
type: mechanic
id: detective--family-22
lang: en
title: Inferring hidden rules
summary: >-
  In a speculative or systemic mystery, the player first discovers world rules
  and then uses them to explain an event.
updatedAt: '2026-10-22'
status: active
url: 'https://gamemechanics.pro/en/knowledge/mechanic/detective--family-22/'
jsonUrl: >-
  https://gamemechanics.pro/api/v1/knowledge/en/mechanic/detective--family-22.json
markdownUrl: >-
  https://gamemechanics.pro/content/knowledge/en/mechanic/detective--family-22.md
aliases: []
tags:
  - Detective games
  - Hypotheses and reasoning tests
sourceIds:
  - source-248d0f12871f66ae
sources:
  - id: source-248d0f12871f66ae
    title: Return of the Obra Dinn
    url: 'https://store.steampowered.com/app/653530/'
    verifiedAt: null
relations: []
placements:
  - catalogId: detective
    id: family-22
    title: Detective games
    url: 'https://gamemechanics.pro/en/mechanics/detective/#family-22'
    categoryIds:
      - reasoning
supersededBy: []
attributes:
  preview:
    updatedAt: '2026-10-22'
    title: Inferring hidden rules
    description: >-
      In a speculative or systemic mystery, the player first discovers world
      rules and then uses them to explain an event.
    image:
      src: images/mechanics/adventure-obra-dinn-01.webp
      width: 1440
      height: 810
      game: Return of the Obra Dinn
      sourceUrl: 'https://store.steampowered.com/app/653530/'
      originalUrl: >-
        https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/653530/ss_380dc35237fde7d3863a44270abafc37924d1db4.1920x1080.jpg?t=1686697594
      credit: Lucas Pope / 3909
      rights: >-
        Game imagery © its respective rights holders. Publisher-distributed
        Steam screenshot; all rights reserved. Excluded from MIT and CC BY 4.0.
      caption: A watch beside the remains opens a scene from the past
      alt: A pocket watch and human remains on the Obra Dinn’s deck.
      markers:
        - x: 36
          'y': 66
          label: The watch opens a memory of the event
        - x: 64
          'y': 56
          label: The remains connect the scene to a participant
    tips:
      - Apply a fictional rule consistently when testing different events.
    examples:
      - title: Return of the Obra Dinn
        url: 'https://store.steampowered.com/app/653530/'
endsAt: null
provenance: >-
  Original editorial taxonomy authored for gamemechanics.pro on 2026-10-19.
  Primary developer and publisher sources support specific released-game
  examples, not the whole classification; design examples are hypothetical.
license: CC-BY-4.0
codeLicense: MIT
attribution: gamemechanics.pro contributors
catalogKey: catalog/detective
---
# Inferring hidden rules

id: detective--family-22
type: mechanic
key: mechanic/detective--family-22
lang: en
status: active
url: https://gamemechanics.pro/en/knowledge/mechanic/detective--family-22/

In a speculative or systemic mystery, the player first discovers world rules and then uses them to explain an event.

## At a glance

![A pocket watch and human remains on the Obra Dinn’s deck.](https://gamemechanics.pro/images/mechanics/adventure-obra-dinn-01.webp)

[Return of the Obra Dinn](https://store.steampowered.com/app/653530/) · Game imagery © its respective rights holders. Publisher-distributed Steam screenshot; all rights reserved. Excluded from MIT and CC BY 4.0.

1. The watch opens a memory of the event
2. The remains connect the scene to a participant

- Apply a fictional rule consistently when testing different events.

- [Return of the Obra Dinn](https://store.steampowered.com/app/653530/)

## How it works

In a speculative or systemic mystery, the player first discovers world rules and then uses them to explain an event.

## Variants

### Variants

<a id="family-22-branch-1"></a>

- Induction from examples: find a rule that explains several observations. <a id="family-22-variant-1"></a>
- Counterexample: test a rule on a new case and refine its limits. <a id="family-22-variant-2"></a>
- Knowledge as a key: apply an understood rule to reach information without acquiring a new item. <a id="family-22-variant-3"></a>

## Design example

A device marks only one kind of material. Several demonstrations establish whether it could have produced a discovered trace.

## Context and limits

A working map of detective design: 32 families and 96 variants. The core loop is to find information, form a hypothesis, test it and explain a conclusion. Answer formats, hints and investigation structure are treated separately. Families overlap, design examples are hypothetical, and released-game examples cite primary sources without revealing case solutions.

## Connected materials


## Sources and provenance

Original editorial taxonomy authored for gamemechanics.pro on 2026-10-19. Primary developer and publisher sources support specific released-game examples, not the whole classification; design examples are hypothetical.

- [Return of the Obra Dinn](https://store.steampowered.com/app/653530/) (id: source-248d0f12871f66ae)

CC-BY-4.0 · gamemechanics.pro contributors