Abstract
The classical doctrine that the moral virtues are unified is widely rejected. Some argue that the virtues are disunified, or even mutually incompatible. And though others have argued that the virtues form some sort of unity, these recent defenses of unity are always qualified, advocating only a partial unity: the unity of the virtues is limited to certain practical domains, or weak in that one virtue implies only moral decency in the fields of other virtues. I argue that something like the classical doctrine—a full unity of the virtues thesis—remains defensible. After reviewing the arguments of partial unity theorists for the claim that the virtues form at least some sort of unity, I examine their main arguments for thinking that this unity is only partial (limited or weak). I then show that these arguments fail, and address some further criticisms (such as the argument that full unity implausibly requires that a person must attain the virtues “all at once”). I do not seek here to prove the truth of the full unity thesis (in fact I suggest a modification of it), but only to refute important extant criticisms of it, and thus to show that it remains a plausible view.