No-Harm Argument


P1. Society should permit people to marry whoever they want unless it is shown to cause harm to others

P2. Same-sex marriage is not shown to cause harm to others

C. Therefore society should permit same-sex marriage


This argument is also used for:

This argument is a form of John Stuart Mill’s “Harm Principle” in which individuals should be free to act however they wish unless their actions cause harm to somebody else.

The first premise assigns the burden of proof to the opponent of permitting any form of marriage but this is the sign of an immature society. If we grant the first premise for the sake of argument, it is certainly not true that same-sex marriage does not cause harm to others (however minimal), even though it may not always be easy to show especially in the short-term.

From Lynn D. Wardle:

Helping people to see that legalizing same-sex marriage or marriage equivalent domestic relationships is an attack on marriage is not easy. The harm it causes is not like a broken bone sticking through the skin or blood pouring from a severed artery. It is more gradual and subtle. It is like the dangers of smoking—the damage is not obvious at first, and by the time people realize that smoking is harmful to them, irreversible damage has often been done (they may have cancer, emphysema, heart attacks, or strokes)

Wardle, Lynn D. (2007) “The Attack on Marriage as the Union of a Man and a Woman,” North Dakota Law Review: Vol. 83 : No. 4 , Article 5.
Available at:

The following arguments propose harm caused by same-sex marriage: