world-building-logic

name	world-building-logic
description	Engineers internally consistent fictional worlds using Brand's Pace Layers for social structure and Sanderson's Laws of Magic for system constraints. Use when building settings, designing magic or tech systems, or auditing a world for logical contradictions.
license	MIT
compatibility	Claude Code and compatible agent products
metadata	{"type":"domain","family":"narrative","rigor":"standard","keywords":"consistency, world-building, internal-logic, setting, magic-system, design","requires":"","enhances":"fiction-architect, character-vulnerability, prompt-optimizer","sources_pdf":"How Buildings Learn (Brand), Science of Storytelling (Storr), The Hero With a Thousand Faces (Campbell)","sources_web":"Sanderson magic system lectures"}

Overview

World-building logic is the engineering of "internal consistency." It moves beyond mere imagination to create a setting that feels "lived-in" and logical. By applying Brand's Pace Layers to social and physical structures and Sanderson's Laws of Magic to the world's limitations, the builder creates a "controlled hallucination" that supports rather than distracts from the plot.

Guiding Principles

Principle 1: The Six Pace Layers (Source: Brand, How Buildings Learn)

A world is not a static monolith; it is a stack of layers moving at different speeds:

1. Site: The eternal (geography, climate).
2. Structure: The centuries (foundations, deep traditions).
3. Skin: The decades (exterior appearances, fashion).
4. Services: The years (infrastructure, technology, systems).
5. Space Plan: The months (interior layouts, social groups).
6. Stuff: The daily (ephemera, personal belongings). Friction (Shearing) occurs where a fast layer (Technology) tries to override a slow layer (Geography).

Principle 2: Limitations > Powers (Source: Sanderson, magic lectures)

Internal consistency is defined by what characters cannot do. A character with unlimited power has no story. Drama is found in the clever application of a world's specific limitations. The more powerful the tool (magic/tech), the more restrictive the rules must be.

Principle 3: Environmental Storytelling (Source: Storr, Science of Storytelling)

The world is an extension of character. Use "Behavioural Residue" (clues left behind) and "Identity Claims" (broadcasted symbols) to show the history of a setting. Instead of telling the history of a city, show a "High Road" monument next to a "Low Road" slum.

Principle 4: The Understanding Threshold (Source: Sanderson, magic lectures)

An author's ability to solve a conflict with a world-rule is proportional to how well the reader understands that rule.

• Hard Systems: Rules are known; the solution is a logical payoff.
• Soft Systems: Rules are mysterious; the solution must be character-driven, not rule-driven.

Principle 5: The "Known" vs. The "Unknown" (Source: Campbell, Hero With a Thousand Faces)

A world must have an "Ordinary" logic and a "Special" logic. The transition between them (The Threshold) must be marked by a shift in rules, stakes, or environment.

When to Use This Skill

• Designing a fantasy world, magic system, or sci-fi infrastructure.
• Establishing the "social rules" of a specific historical or corporate setting.
• Troubleshooting "Deus Ex Machina" plot points where world-rules feel arbitrary.
• Mapping the geography or history of a long-form narrative.

When NOT to Use This Skill

• Writing minimalist "slice-of-life" fiction where the world is exactly as the reader's own.
• Ideation phases where "cool ideas" should flow without immediate logic-checking.

Core Process

Step 1: Establish the "Site" and "Structure" (Source: Brand)

Define the physical and social constants that cannot be easily changed.

• What is the geography?
• What are the deep, unchanging traditions?
• This layer provides the "Gravity" of the world.

Step 2: Define the Limitations (Source: Sanderson)

Before giving a character a power or a tool, list the three things it cannot do and the cost of using it.

• Cost could be physical, social, or moral.
• A rule with no cost is a plot-killer.

Step 3: Map the Shearing Layers (Source: Brand)

Identify where the world is changing too fast for its foundations.

• E.g., A digital economy trying to function in a medieval castle.
• This friction is the primary source of world-based conflict.

Step 4: Flesh out the "Stuff" (Source: Storr)

Add specific, sensory details. Use the "Rule of Three Qualities": a "heavy, tarnished, silver locket" is more real than a "pretty locket." These details must reveal character history (Environmental Storytelling).

Step 5: Test the Logic Chain (Source: Sanderson)

Take a world-rule to its logical conclusion. If people can fly, how does that affect the architecture? If people can read minds, how does that affect the justice system? Consistency comes from these "second-order effects."

Frameworks & Models

Sanderson's Laws of Magic (Source: Sanderson, magic lectures)

1. First Law: Capability to solve conflict is proportional to user/reader understanding.
2. Second Law: Limitations > Powers.
3. Third Law: Expand on existing elements before adding new ones.

The Six S's Hierarchy (Source: Brand, How Buildings Learn)

• Slowest: Site -> Structure -> Skin -> Services -> Space Plan -> Fastest: Stuff.
• Rule: Slow components dominate and constrain rapid ones.

Cross-Skill Invocations

REQUIRED SUB-SKILL: fiction-architect — to integrate world-rules into the plot. RECOMMENDED SUB-SKILL: prompt-optimizer — to translate world-building logic into consistent AI character personas or descriptions.

Common Mistakes

1. World-Building Disease: Focusing on the "Site" and "Structure" (history/maps) while ignoring the "Stuff" and "Space Plan" (daily life/character experience).
2. Arbitrary Rules: Changing the world's logic halfway through to help the protagonist escape a corner. (Source: Sanderson)
3. Floating Setting: The world feels like a neutral backdrop rather than an active character that constraints the plot. (Source: Storr)

Diagnostic Checklist

• Are the world's limitations more clearly defined than its powers?
• Does the setting reflect the history and psychology of the characters?
• Is there a clear logical consequence for every rule established?
• Does the world have both "High Road" (stable) and "Low Road" (adaptable) elements?
• Have I cross-checked the "second-order effects" of the technology/magic?

Sources

• Brand, Stewart. How Buildings Learn. Ch. 2 (Shearing Layers), Ch. 3-4 (Low Road/High Road).
• Storr, Will. The Science of Storytelling. Ch. 1 (Creating a World).
• Campbell, Joseph. The Hero With a Thousand Faces. Ch. 1 (The Call to Adventure).
• Sanderson, Brandon. "Laws of Magic" (BYU Lectures).