I think the best way to summarize the links between freedom and flourishing is by trying to answer the following questions.
1. What is the relationship between happiness, well-being and flourishing?
If happiness is viewed as a positive emotional state (involving, for example, peace of mind, optimism, uncompression, exuberance, flow, joy and cheerfulness) then well-being (utility) cannot be the same thing as happiness. (See: What is happiness? and Do good decisions always make us happy?) Well-being (utility) involves several other factors - including personal security and security of property, health and longevity, access to goods and services – as well as a positive emotional state.
Flourishing can be described as authentic well-being. I am attracted to the idea that flourishing involves self-fulfillment as well as to the idea that it involves a meaningful life and actualization of human potential. It seems to me that the highest level of reflection of a flourishing person would be in harmony with his or her emotional nature, and vice versa (but I don’t claim to know a great deal about this ideal frame of mind or meta-state).
2. What is the relationship between freedom, classical liberalism and rationalistic individualism?
Freedom (liberty) is the condition of society in which the coercion of some by others is reduced as much as possible. It seems to me that classical liberalism is essentially about the rule of law and the protection of freedom. It is the view that people can live together in peace and to their mutual advantage bound only by abstract rules of conduct that protect the life, liberty and property of each person.
It is important to distinguish between rationalistic individualism and classical liberalism. Whereas rationalistic individualism maintains that a person’s wellbeing always increases when he or she has more options to choose from (liberal optimism), classical liberals have a more sober view of human nature. For example, Adam Smith accepted human fallibility but believed that the desire that individuals to better their own condition would generally prevail over their tendency to be prodigal and imprudent. (See: Liberal sobriety plus contextualism equals classical liberalism? and Is freedom a necessary condition for human flourishing?)
Various attempts have been made to measure freedom. The most relevant for present purposes are economic freedom indexes that measure the extent to which economic policies support private property, personal choice, voluntary exchange, freedom to compete etc.
3. What is the relationship between freedom and happiness?
People generally have a passion for control of their own lives. (See: Does inner freedom link liberty with flourishing?) Most people enjoy exercising competence in the face of the challenges that freedom poses. Exercising such competence is no easy matter; people often become unhappy as a result of the poor choices they make. But people whose life stories that are full of challenges, setbacks and triumphs may be happier than those whose lives are uniformly secure, comfortable and tranquil. (See: Does a challenge make us happy?)
The exercise of freedom can result in economic developments that disrupt communities, cultures and lifestyles, and leave many people unhappy. Such problems can be minimized under appropriate constitutional arrangements that decentralize political decision-making (See: Do we have to choose between lifestyles and liberty?)
Inner freedom – the extent to which people feel in control of their own lives – seems to be closely related to the emotional states involved in happiness. The proportion of the population with high levels of inner freedom tends to be higher in countries with higher levels of economic freedom. (See: Is inner freedom related to economic freedom?)
4. What is the relationship between freedom and well-being?
Freedom (as defined above) is inextricably linked to security of persons and property.
The relationship between economic freedom and other aspects of well-being was discussed in my post: What do objective measures of freedom and flourishing tell us?.