Full Idea
An analysis of virtue is hopeless unless we can assume that most of a selected list of traits count as virtues, in a way not strictly culture. ...These would include wisdom, courage, benevolence, justice, honesty, loyalty, integrity, and generosity.
Gist of Idea
Virtue theory is hopeless if there is no core of agreed universal virtues
Source
Linda Trinkaus Zagzebski (Virtues of the Mind [1996], II 2.1)
Book Reference
Zagzebski,Linda: 'Virtues of the Mind' [CUP 1996], p.89
A Reaction
This requirement needs there to be a single core to human nature, right across the species. If we are infinitely flexible (as existentialists imply) then the virtues will have matching flexibility, and so will be parochial and excessively relative.