Habermas said a norm is only truly valid if it could survive a totally fair argument

Jürgen Habermas argued that a moral or political rule is legitimate only if everyone affected could agree to it in a free discussion among equals, with no coercion, deception, or unequal power distorting the outcome. He called this the ideal speech situation. Real debates never fully reach it, but for Habermas it's the standard that tells you whether an agreement earned its legitimacy or just reflects who had the most power in the room.

— Jürgen Habermas, Moral Consciousness and Communicative Action — 1983, trans. 1990
Go deeper: get the book →