Economic systems are part of social systems because they involve relationships and interactions among people; and these in themselves are not always easy. In a materially ideal world, economic arrangements would be unnecessary because everyone would have what they needed and wanted without having to trade or work for it other than to go out and pick it up. But in the real world, not only are material goods difficult to produce, but producing and distributing/acquiring them requires social arrangements, which themselves are often difficult to construct and keep harmonious (1) due to lack of agreement in some cases about which goals or means of achieving them are best and most just and fair, (2) due to misunderstandings about expectations, and (3) due to unforeseen consequences, particularly those in a complex interactive, continually adaptive environment or mechanism where any change in one part of the system has effects that can ripple throughout the system causing further changes and then changes in response to those . Some of these effects may even occur without their distant or ultimate causes' being noticed or readily traced and discovered.

Moreover, there is a difference between harmony engendered by mere compatibility and harmony engendered from compatibility that is also consistent with goodness, beauty, and truth. People engaged in a terrible act can be quite compatible and act in great concert to achieve deplorable goals, even in deplorable ways, often thinking they are behaving properly and reasonably. It is not easy to know what is right or even reasonable, and it is not easy to convince others (or to be convinced by others) when someone does know what is right or reasonable. So even if a society has operating, harmonious, compatible working and trading relationships in an economic system, that does not necessarily mean they have a system that best serves its members, even if the members think it does and even if they are happy. One, of course, is considered either an elitist or at least a meddler when one tries to tell someone else, or a whole society they are not doing what they could and should be doing, or that their system is not working as well as they think it is. But being convincing in any particular case is a matter of social psychology more than it is a point that is conceptually incomprehensible for people to understand in general. It is fairly easy to show people that happiness alone is not the hallmark of doing the right thing, especially if you point out to them people who are happy that you know they believe are only happy out of ignorance, or who they believe are unfairly or undeservedly happy. The difficulty is not in explaining the concept but in trying to convince people that it applies to some particular belief and behavior of theirs. And, of course, one could always be mistaken in thinking the other person or the other society is mistaken. Knowing what is right and what is best are not always easy things to know or to discuss clearly, coherently, reasonably, and reasonably dispassionately.

Because of all this, economics as a practice is even more difficult than just discovering better ideal theories or principles of division of labor and trade. Centralized economies or businesses face problems of motivation, innovation, and responsiveness to important (often subtle) operating conditions and client/colleague needs and wishes, particularly during times of change. Furthermore, centralized economies can have bad goals or bad means just as can free market economic systems where everyone is left to their own devices to trade whatever they might wish. Efficiency does not guarantee either quality, fairness, or utility. Free market systems, particularly in diverse, mutually dependent but democratic societies, face a host of problems from the known concerns about "externalities" to problems involving accommodating different social views, goals, and values. Even where all these things can be worked out theoretically, convincing everyone of the theory is not easy, and is often not even feasible, particularly in a heterogeneous, democratic society. While competition in a free market may benefit future generations or even current members of society as consumers, it often wreaks havoc on contemporary individuals and companies as providers and competitors. While the stability of a satisfactorily functioning centralized economy in a homogeneous society can breed stagnation, the progress potentially inherent in a free market, democratic society, particularly in times of swift scientific/engineering or social advances and changes, can be socially problematic, disruptive, and even destabilizing.

The ideal, of course, is to have the potential freedom and adaptive innovation of a free market economy with the social stability and potential fairness of a more controlled economy and society. Theoretically that can be achieved in a free society where everyone has sufficient knowledge of conditions and mechanisms and where everyone's individual desires actually reflect the most desirable values, goals, and quality of life, and the most desirable means of achieving them. That will require science and philosophy to provide the requisite information, perspective, and wisdom, information technology to make it available to everyone, and a good educational system to insure people can understand and appreciate it and respond to correct it where necessary. One sees rare glimpses of it in those communities or institutions where leadership makes manifestly available direction and explanations which are reasonable, knowledgeable, articulate, dynamic, believable, and persuasive, and where citizens are concerned, attentive, responsive, and knowledgeable and wise enough to distinguish good ideas from bad ones.