When a univocal genus is divided into its species, the members of the division are on a par in the point of the generic idea; although considered in their nature as things, one species may surpass another in rank and perfection, as man in respect of other animals. But when we divide an analogous term, which is applied to several things, but to one before it is applied to another, nothing hinders one from ranking before another, even in the point of the generic idea; as the notion of being is applied to substance principally in relation to accident. Such is the division of virtue into various kinds of virtue: since the good defined by reason is not found in the same way in all things.
Thomas Aquinas, ST 1-2ae.61.1 ad 1
