Economics / Public Policy / Systems
Economics / Public Policy / SystemsLighthouse Effect
A lighthouse helps every passing ship without charging any of them.
Popularity
Usefulness
Aliases
Public-good principle / shared-benefit rule
Domains
Economics, public policy, management, systems
Definition
- The Lighthouse Effect describes how some benefits, like a lighthouse's beam, serve everyone freely and cannot easily be withheld — so such shared goods need shared support to exist.
Core Idea
- A lighthouse helps every passing ship without charging any of them.
- Such public goods benefit all but are hard to fund through individual payment.
- Shared benefits require collective support, or they will be under-provided.
How It Works
- A public good is non-excludable: you cannot easily stop non-payers from benefiting.
- Individuals are tempted to free-ride, hoping others will pay.
- Without collective arrangements, the good is undersupplied.
Usage Example
- Clean air, public safety, and basic research benefit everyone but are underfunded if left to voluntary individual payment — so they are supported collectively.
Famous Example
- Example: The lighthouse, a classic economics example of a public good (debated since the work of economists like Coase).
- Why it fits this rule: It illustrates non-excludable, shared benefits.
- Verification status: A standard (and debated) example in public-goods economics.
Use Cases / Situations Where It Applies
- Understanding public goods and free-riding.
- Designing collective funding.
- Shared infrastructure and resources.
When Not to Use or Common Misuse
- Do not assume all goods are public goods.
- Do not ignore that some "public goods" can be privately provided in certain conditions.
- Do not overlook free-rider problems in shared efforts.
Rule Invention / Origin
- Invented by: A standard economics example; the lighthouse case is widely discussed.
- Year of invention: Classic economics concept.
- Country / context of origin: Economics literature.
Evidence / Research Basis
- Grounded in public-goods economics and the free-rider problem.