> When the ability to debate is removed, the only thing remaining is force. You seem to be conflating the ability to debate with the existance of objective eth

> When the ability to debate is removed, the only thing remaining is force. You seem to be conflating the ability to debate with the existance of objective ethical facts. That sounds like a bit of a false choice to me. What kind of ethical experiment would reveal an ethical truth in the same way in which jumping of a cliff reveals a physical truth? It also strikes me that our belief that slavery is wrong is not really hostage to experiment in the same way in which my belief that gravity exists is. What kind of fact would you have to be confronted with to recognise that your belief ('slavery is wrong') is false?