 Whether or not there are any properties or entities with anything like the powers Mackie describes, it is a mistake to suppose that moral realists and objectivists must be committed to their existence. No realist or objectivist need think that moral properties, or facts about their instantiation, will, when apprehended, be sufficient to motivate all persons regardless of their circumstances, including their cognitive and motivational makeup. And realists certainly need not take the view that Mackie ascribes to Plato, that seeing objective values will ensure that one acts, “overruling any contrary inclination” (Mackie 1977,23). An individual might grasp a moral fact, for example, but suffer from temporary irrationality or weakness of will; she might be free of such temporary defects but possess a more indelible motivational makeup that impedes or defeats the motivating power of moral facts. Any plausible account of moral motivation will, and must, acknowledge these sources of motivational failure; and any plausible analysis of moral properties must allow for them. Even those realists or objectivists who maintain that all rational and motivationally unimpaired persons will be moved by moral facts need not think they will be overridingly indefeasibly motivated. As already noted, regardless of their views with respect to broader metaethical questions, contemporary philosophers do not take any position on the precise strength of moral motivation—with the qualification (alluded to earlier) that they reject, apparently universally, the idea that moral motivation is ordinarily overriding.