  Much of the contemporary metaethical discussion about moral disagreement is inspired by John Mackie’s “argument from relativity”, which is offered in support of his nihilist metaphysical claim that there are no moral facts. Mackie’s argument is often interpreted as an inference to the best explanation. On that interpretation, the existence of widespread moral disagreement supports the thesis that there are no moral facts because it is implied by the best explanation of the disagreement. However, although that construal of Mackie’s argument is quite common (e.g., Brink 1989, 197; McGrath 2008, 90; Joyce 2010, 46 (but see also Joyce 2018); Vavova 2014, 304; and Clarke-Doane 2020, 148), it is also questionable.