What is the open question argument?

What is the open question argument?

The open question argument is an argument in metaethics that challenges the idea that moral properties can be reduced to natural or descriptive properties. It argues that no matter how much we know about the natural or descriptive properties of an action or object, it still remains an open question whether it is morally good or bad. This suggests that moral properties are distinct and cannot be fully explained or reduced to non-moral properties. The open question argument highlights the difficulty in bridging the gap between descriptive and normative claims, and supports the view that moral properties are irreducible and objective.