Brandon Sanderson, one of fantasy’s most prolific worldbuilders, articulated something that had been true of great fantasy for decades but rarely stated explicitly:
Magic isn’t about being magical. It’s about being a tool for storytelling.
And like any tool, magic systems work better when they follow certain principles.
Sanderson codified these into what’s now known as Sanderson’s Laws of Magic. They’re not rigid rules but design principles that help you create magic systems that serve your story instead of undermining it.
Let’s break them down-and then go beyond them.
Sanderson’s First Law
“An author’s ability to solve conflict with magic is directly proportional to how well the reader understands said magic.”
What This Means
If magic is mysterious and unexplained, you can’t use it to resolve major plot conflicts without the reader feeling cheated.
If magic is well-defined and understood, you can use it to solve problems and the reader will feel satisfied.
Why This Works: The Promise of Problem-Solving
When a protagonist faces an obstacle, readers are implicitly asking: How will they get out of this?
If the answer is “a wizard shows up and fixes everything with magic we’ve never seen before,” readers feel robbed. The solution came from nowhere. There was no way to anticipate or understand it.
But if the answer is “the protagonist uses the magic system we’ve been learning about in a clever new way,” readers feel satisfied. The solution was available all along-they just didn’t see the application.
The Spectrum: Hard vs. Soft Magic
Sanderson introduced the terms “hard magic” and “soft magic” to describe this spectrum:
Hard Magic (High Understanding):
- Clear rules, costs, and limitations
- Readers understand how it works
- Can be used to solve plot problems
- Examples: Mistborn, Avatar: The Last Airbender, The Name of the Wind
Soft Magic (Low Understanding):
- Mysterious, unexplained, wondrous
- Readers don’t fully understand how it works
- Cannot solve major plot problems without feeling like cheating
- Examples: The Lord of the Rings, Harry Potter (early books), Studio Ghibli films
Neither is better-they serve different narrative purposes.
Hard Magic Example: Mistborn
In Sanderson’s Mistborn, Allomancy has precise rules:
- Ingest specific metals
- “Burn” them to gain specific powers
- Each metal does one thing
- Powers last as long as you have metal to burn
Because we understand this system completely, Sanderson can write action scenes where Vin uses Allomancy to solve problems, and we’re never confused or feel cheated. We understand exactly what she can and can’t do.
Soft Magic Example: The Lord of the Rings
Gandalf’s magic is never explained. We don’t know his limits. He has different powers in different scenes.
But Tolkien never uses Gandalf’s magic to solve the main plot. The ring isn’t destroyed by magic-it’s destroyed by Frodo’s choice and Gollum’s obsession. Magic creates atmosphere and raises stakes, but doesn’t resolve core conflicts.
This works because Tolkien obeys the First Law: his magic is soft, so he doesn’t use it to solve problems.
The Practical Takeaway
If you want to use magic to solve plot problems: Define the magic clearly. Show the rules. Let readers understand the costs and limitations.
If you want magic to feel wondrous and mysterious: Keep it vague. But don’t use it to get characters out of narrative corners.
Sanderson’s Second Law
“Limitations are more interesting than powers.”
What This Means
The cool thing about your magic system isn’t what it can do-it’s what it can’t do.
Why This Works: Constraints Create Creativity
Stories need obstacles. If magic can do anything, there’s no conflict.
But if magic is powerful within specific constraints, those constraints become the source of dramatic tension.
Superman is boring if he’s invincible. He’s interesting when kryptonite exists, or when he has to save people without revealing his identity, or when the choice is between saving one person or another.
The cost matters more than the capability.
Examples of Great Limitations
1. Full Metal Alchemist: Equivalent Exchange
- You can’t create matter from nothing
- Alchemy requires equal trade
- Human transmutation is forbidden (and horrifically fails)
These limitations drive the entire plot. The protagonists’ quest exists because they violated the rules and paid the price.
2. Death Note
- You must know the person’s face and real name
- You must write the name yourself
- The notebook has a limited number of pages
Light Yagami’s entire strategy revolves around working within these limitations. The cat-and-mouse game with L only works because the Death Note isn’t omnipotent.
3. Avatar: The Last Airbender
- Each person can bend only one element (except the Avatar)
- Bending requires physical movement
- Bending is weakened under certain conditions (waterbenders at day, firebenders during eclipses)
Every fight scene is shaped by these limitations. Toph can’t bend in the air. Katara is more powerful with more water available. Limitations create tactical variety.
The Practical Takeaway
When designing your magic system, spend more time on the costs and limitations than the abilities.
Ask:
- What can’t this magic do?
- What does using it cost (energy, life force, sanity, social standing)?
- Under what conditions does it fail?
- What are the risks of using it?
Sanderson’s Third Law
“Expand what you already have before you add something new.”
What This Means
When your story needs more magical capability, don’t invent a new system. Find new applications of the existing system.
Why This Works: Depth Over Breadth
Readers invest effort in understanding your magic. If you keep introducing new magical elements, you’re asking them to keep learning new systems.
But if you deepen and expand the existing system, readers feel rewarded. “Oh, I understand this! I see how this new application follows from what I already know.”
Example: Mistborn Again
Sanderson doesn’t keep inventing new magic systems in Mistborn. Instead, he reveals:
- New metals with new powers (expanding the existing framework)
- Combinations of metals (Compounding)
- Allomancy applied in unexpected ways
Each expansion feels like “of course”-it’s consistent with what we already know, just deeper or more creative.
Example: Avatar: The Last Airbender
The show doesn’t add new elements. Instead it reveals:
- Specialized sub-skills (metalbending, lightning bending, bloodbending)
- New applications (ice as armor, air as a sphere)
- Bending philosophy (each element has different fighting styles)
All of this emerges from the core concept: people can manipulate elements.
The Practical Takeaway
Before inventing a new magical ability, ask: “Can I achieve this narrative goal by expanding the existing system in a logical way?”
Beyond Sanderson: Additional Principles
Sanderson’s Laws are excellent, but they’re not comprehensive. Here are additional principles:
4. Magic Should Have Cultural Implications
If magic exists, society will shape itself around it.
Example: The Broken Earth trilogy (N.K. Jemisin) Orogenes (people who can manipulate energy) are enslaved because their power threatens society. The entire social structure, architecture, and history revolve around managing this magical underclass.
Magic isn’t just a tool-it shapes economics, politics, religion, and social hierarchy.
Ask yourself:
- Who has access to magic?
- How do the powerful control it?
- How do the powerless protect themselves from it?
- What professions exist because of magic?
5. Magic Should Have Philosophical Coherence
Your magic system should reflect something about how your world works.
Example: Earthsea (Ursula K. Le Guin) Magic in Earthsea is about knowing the true names of things. This reflects the philosophy that to change something, you must understand its essence.
The magic system is the worldview made literal.
Ask yourself:
- What does your magic system say about reality in your world?
- Is magic about force, knowledge, connection, sacrifice?
- Does the magic reflect a philosophy of how change happens?
6. Consistency Matters More Than Realism
Your magic doesn’t have to make scientific sense, but it must make narrative sense.
Example: Harry Potter The magic is often inconsistent (Why don’t they use time-turners to solve every problem? Why is Avada Kedavra unforgivable but Imperio-ing someone into suicide is fine?).
Readers forgive inconsistency when they’re engaged, but it weakens the story.
Ask yourself:
- Have I established how this works?
- Am I following my own rules?
- If I’m breaking a rule, is it for clear thematic/narrative reasons?
7. The Cost Should Be Personal
The best magic systems don’t just have energy costs-they have meaningful costs.
Example: The Powder Mage trilogy (Brian McClellan) Powder mages burn gunpowder for power, which makes them addicts. The cost isn’t just energy-it’s dependency.
Example: A Wizard of Earthsea Using magic disturbs the balance of the world. The cost is ecological and moral, not just energy.
Ask yourself:
- What does the character sacrifice to use magic?
- Is the cost interesting and thematic, or just numerical?
Designing Your Magic System: A Framework
If you’re building a magic system from scratch, consider these questions:
1. Source
Where does magical power come from?
- Internal (life force, willpower, genetics)
- External (gods, nature, artifacts)
- Transactional (bargains, sacrifices)
2. Cost
What does using magic require or consume?
- Energy/stamina
- Sanity/morality
- Life span
- Social capital
- Physical materials
3. Limitations
What can’t magic do?
- Forbidden effects (can’t create life, can’t time travel)
- Conditional failures (doesn’t work on X, fails under Y conditions)
- Unpredictability (has a chance to fail or backfire)
4. Access
Who can use magic?
- Everyone (but to varying degrees)
- Special bloodlines/genetics
- Learned skill (anyone can learn, but it’s difficult)
- Divine selection
5. Cultural Integration
How does society respond to magic?
- Regulated or forbidden?
- Monopolized by an elite?
- Common and everyday?
- Feared and hidden?
Common Pitfalls
Pitfall 1: Overcomplexity
If readers need a glossary to track seventeen different magic subsystems, you’ve lost them.
Solution: Keep the core concept simple. Complexity can emerge from simple rules applied in varied ways.
Pitfall 2: The Deus Ex Machina Spell
Suddenly revealing that magic can do something convenient we’ve never seen before.
Solution: Establish capabilities early. If a spell will solve the climax, show it in Act One.
Pitfall 3: Ignoring Implications
Creating a magic system that should reshape society, then depicting a medieval Europe clone.
Solution: Think through the second-order effects. How would this magic change warfare, communication, transportation, social hierarchy?
Pitfall 4: Magic Without Wonder
Hard magic systems can become so mechanical they lose the sense of the numinous.
Solution: Even well-defined magic should feel a little awe-inspiring. Describe the experience, the sensation, the cost.
The Ultimate Test
A great magic system serves your story, not the other way around.
Ask:
- Does this magic create interesting conflicts?
- Does it raise the stakes rather than lowering them?
- Does it force characters to make difficult choices?
- Does it reveal something about theme or character?
If yes, your magic system is working.
If no, it might be time to rethink the rules.
Final Thought
Magic is worldbuilding’s most powerful tool-and its most dangerous.
Done well, it creates wonder, conflict, and thematic resonance.
Done poorly, it’s a shortcut that undermines narrative tension.
Follow Sanderson’s Laws. Understand the costs and limitations. Think through the implications.
Then write magic that feels magical and earned.
Next in the series: The Lived-In World - How details of wear, grime, and history make settings feel authentic and pre-existing.