The state and practices of living in an ideal situation of being healthy, happy, and prosperous, arising from and maintained by actions that result in that state of individual well-being. This definition attempts to capture the overlapping senses of the word when originally used by Aristotle. That word referred as much to the practices of life as to the ideal state of living. While this is sometimes proposed as a goal for all research, that it should contribute towards the achievement of an ideal condition for humanity, it is not clear that there is, or could be, sufficient agreement on what the key terms mean when they have to be translated from abstractions into actual living conditions.