To grasp the importance of ethical reasoning, it is necessary to understand a particular notion of ethical philosophy and its implications. Ethics is here construed as virtuous behavior and as a component of the larger notion of what constitutes a good life. But this notion of ethics should be only the starting point for a rigorous, and-I will argue-beneficial, process of reasoning and self-examination. The practical reasoning of ethics and virtue is grounded in our personal valuations of such qualities as happiness, freedom, autonomy, duty, and rationality. At least since Socrates (c. 470-399 B.C.), the definition of virtue has been a persistent question in Western philosophy; so too has the question of what constitutes a life well lived. Aristotle (384-322 B.C.), for example, begins his Nicomachean Ethics with an analysis of human happiness, which he suggests should be the aim of virtuous behavior.