The Harm Principle

Mill asks when it is right to limit a person’s freedom. His answer is the harm principle: the only good reason to interfere with someone against their will is to prevent harm to others. A person’s own good, physical or moral, is not enough.

This protects choices that others may find foolish, such as an unusual diet, an odd hobby or an unpopular opinion. It does not protect harming others, which is why midnight noise and fraud are fair to restrict. The hard cases are harms that are small, shared or disputed.

Use it as a test. Name the harm, name who bears it, and ask whether it is more than offense or disapproval. If nobody is harmed, ask whether the rule only enforces a taste. If someone is, ask whether the restriction is the least that would protect them.

The neighbors’ rules

A neighborhood committee proposes banning front-yard vegetable gardens because some residents think they look untidy. Another rule would limit amplified music after ten at night.

The committee applies the test. Untidiness is a matter of taste that harms no one. Late music costs neighbors their sleep, which is a real harm. They drop the first rule and keep a softer version of the second, with a clear start time.

Try this today Before you back a rule, name the harm it prevents and who bears it.