Is there anything more than a verbal difference between the notion of “well-being” and the notion of “flourishing”?
I think there is. But it makes only sense to analyze the nature of this distinction by looking at the
conceptual connection between well-being/flourishing and other elements of the philosophical theories to which they belong. It is not enough to question our common-sense intuitions about the two notions: the difference between the two is too subtle to be discovered in this way.
Both notions concern the idea of a good life, in some sense. But “well-being” is normally used by welfarist utilitarians and welfarist that are deeply influenced by that tradition (e.g. the majority in the English speaking tradition) to refer to a notion of the “good” which makes most sense of a dichotomy between “personal well-being” on one side and “the well-being of others” on the other. To put it in a diagram, it is something like:
with personal well-being and morality conceived as two distinct values or goals. The promotion of personal well-being is conceived as the goal of prudence or practical rationality, when the latter is narrowly conceived. It is the sort of theoretical object that allows to describe the problem called “prisoner's dilemma”.
The notion of flourishing is used mostly by Aristotelian philosophers. It indicates the good life in a somewhat broader sense than well-being. It corresponds to a life in which the different needs of a being that is rational and social are satisfied and in equilibrium. It assumes at the outset that a human being is a social animal and that it can develop well only in a context which develops well. In a diagram:
Flourishing is understood as a broader notion of the quality of life, which includes all those activities which are human beings in general exercise, and that are part of what makes them human. Since some of these activities are not self-interested ones, or are forms of altruistic behavior, the relation of flourishing to the virtues and to forms of behavior that are not clearly self interested is one of part to whole.