In our case the guidance of nature is to pursue pleasure and avoid pain, so whatever choices in reality and in total effect achieve that goal should be considered virtuous.
I'm getting hung up on the word "virtue" and it's meaning.
Cassius it seems like instead of this sentence ending in "virtuous" it could end in the word "good" or "beneficial".
I haven't studied enough to know what all of the various ancient Greek philosophers said, but here are some Wikipedia entries on modern understanding of virtue(s).
Here is Wikipedia on virtue:
QuoteA virtue (Latin: virtus) is a trait of excellence, including traits that may be moral, social, or intellectual. The cultivation and refinement of virtue is held to be the "good of humanity" and thus is valued as an end purpose of life or a foundational principle of being. In human practical ethics, a virtue is a disposition to choose actions that succeed in showing high moral standards: doing what is said to be right and avoiding what is wrong in a given field of endeavour, even when doing so may be unnecessary from a utilitarian perspective. When someone takes pleasure in doing what is right, even when it is difficult or initially unpleasant, they can establish virtue as a habit. Such a person is said to be virtuous through having cultivated such a disposition. The opposite of virtue is vice.