VALUES & SUSTAINABILITY
Large groups of humans living together, including large human societies, develop values and rules that follow from those values that to some degree provide for the welfare, sustainability, and survivability of the group or the groups perish. As the elites in the society generally design, implement, and enforce the rules, they feel constant internal pressure to mold the rules to serve their own narrow interests and external pressure to develop rules that serve the broader interests of the entire society, i.e., more utilitarian rules. This results in a a set of rules that contains some rules for the exclusive benefit of the elites and other rules for the benefit of the whole, including non-elites.
However, if the external pressure is reduced in some way, for example if the elites become more insulated because of the accumulation of wealth or other forms of power, then the balance is tilted towards the values and narrow rules that only serve their interests. This can create self-reinforcing feedback loops as these self-serving rules may accelerate the accumulation of wealth and power of the elites. This leads to the deterioration of the welfare of the non-elites, which eventually leads to general societal deterioration which even impacts the elites, regardless of the degree to which they have insulated themselves from the problems and suffering of the non-elites. Unless this societal deterioration is addressed rapidly and forcefully, the economy of the society and the society itself begin to disintegrate and develop runaway feedback loops of self-destruction, caused by ever narrowing self interest, leading to complete disintegration and collapse.
Also note that while civilization offers a great improvement in the quality of life for humans, it is at the cost of suppressing certain behavioral trends and desires that naturally occur (that would be consistent with group survival and welfare in a small hunter-gatherer group but inconsistent with group survival and welfare in a large, complex civilization). The best minds of most generations throughout the thousands of years of civilization have agreed that the benefits of civilization far outweigh the costs, but because of a confluence of several different forces many influential individuals in Western societies, particularly the United States, during the past few decades have become convinced that the benefits are not worth the costs and have successfully brought pressure to discard or reduce the civilized values, i.e., those that benefit the general welfare, from society.
VALUES & POSTMODERNISM
A positive contribution to the debate about the difficulty in achieving a broad consensus on optimal policy choices has been made by postmodernists who have promoted the idea that there are an infinite number of possible values, and goals based on those values, which means it is impossible to determine a policy choice that is in accordance with all of them. This is in contradiction to what had been a popular idea that science alone, through the use of a scientific positivist approach, could lead to universally agreed-upon optimal policy decisions, at least from a utilitarian perspective.
Where postmodernists fail is where they assume that individuals are connected to a set number of groups based on a set number of characteristics and this determines what they value or have the potential to value, when humans are much more flexible than that as any individual will value that which the individual is connected to through experience and that which the individual speculates or imagines that the individual will be connected to in the future.
So one key to being able to consistently develop consensus on policy choices is to design a system where people are more likely to be connected to and to value what other people are more likely to be connected to and to value so that they can agree on values and thereby on goals in a sustainable fashion. The design would need to take into consideration the likely experiences of the population, important aspects of the cultural and physical environment the population inhabits, human neurological and physical development with a consideration of evolutionary pressures providing insight to the potential for developing particular connections, including the pressures for survival and reproduction. The other key, consistent with the approach of scientific positivism, is to ensure that this system is in harmony with what is understood about Nature, ensuring that its positive feedback loops are consistent with those of the natural world, so that it is sustainable with regard to Nature.
On the related topic of happiness, I would add that a useful model of the phenomenon would be to think of it as the creation and maintenance of sustainable positive feedback loops in neural circuits in the brain, recognizing that such circuits cannot last indefinitely* as the circuits become satiated or acclimated to the feedback, and there must be a change in order to maintain the level of excitement. Success in achieving and maintaining an appealing level of happiness would involve development of healthy behavior patterns in harmony with the in-brain neural environment and the external environment, including the brains of others in the social group. Harmony with the external environment may be achieved either through adapting the brain to be consistent with that environment or by modifying that environment to be consistent with the brain, and in the social group part of the external environment, it would mean the development of appropriate rules to maintain social harmony.
* As a side note, since there is no algorithm for success or any behavior that is universally healthy and productive in a world of unbounded complexity, it is advantageous that positive feedback loops in the brain do not appear to be designed to last indefinitely, as adaptive change is necessary to survive.