Final answer:
Aristotle is the prominent ethicist who extensively about virtue ethics, particularly in his work, the Nicomachean Ethics, focusing on the cultivation of virtuous character traits.
Step-by-step explanation:
One prominent ethicist who wrote extensively about virtue ethics was Aristotle. Aristotle's approach to ethics is characterized by a focus on developing virtuous character traits to live a flourishing life, as detailed in his work, the Nicomachean Ethics. His ethics is grounded in the practicalities of human existence and the cultivation of aretê (excellence or virtue), asserting that the function or purpose of a thing determines its virtue.
Furthermore, Aristotle's ethics have been influential in the development of moral philosophy, though they have also been critiqued by modern philosophers for vagueness and applicability. Still, his work remains a cornerstone in the study of virtue ethics, taking a character-centered approach to morality where right action is seen as stemming from a well-developed character.