So what are virtues and why do we need them?

We can offer a very quick and easy answer to that question by simply going to the first three articles of question 55 of the prima second of the summa theologia.

Article 1 says that a virtue most generally conceived is a perfection of a power.

And then he goes and specifies what that means.

In the case of human powers, it's an operative habit, and not just any type of operative habit,

a good operative habit that perfects that power for good action,

that disposes us, as we learn later on in those questions,

to do the good act with ease, promptness, and joy.

So why do we need them?

He also already, in Article I, says, well,

because the powers are general.

They're ordered to a general level of action, but action is specific.

So we need something that will dispose us not to act in general, no one acts in general,

but to act here and now, Hick et Nuk, something that disposes us to act well, to do the good act

concretely.

And since angels and God are in perfect act, so their virtus is activity itself,

but that's not the case for us.

Other powers are determined to their action, but these powers of the soul, intellect, will, the passions,

especially as they're subdivided into the irascible and concupiscible appetites,

those powers are not specified to their concrete actions.

So something in between the power and the act has to intervene to dispose us to act well.

So a virtue in its fullest definition would be, or at least generic definition,

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