So What is Reason?
Short answer: it's not totally clear.
Interestingly, there's reference to right and wrong as being faculties of reason, which is tremendously presumptuous - there is no such thing in a materialistic account of existence - but many seem to have a strong desire to see morality as a process of reason. Even if they have the sense to use consequentialist understandings of right action in most cases, philosophers often refer to a "general good" or a "collective morality" of some kind which is poorly defined. I would define it by the popular conception of right and wrong in the free markets of ideas, but calling it a dominating cultural product undermines its validity and authority for some people who really, really want moral righteousness to be an objective reality. Here, the perceived difference between logic and reason is telling. Logic, the process of inferring one thing from another, is seen as being both a product of reason and a condition of reason, so there are some questions as to which is the element of the other. Here's how I see it.
As I have said before, you can boil most mental activity down to two processes: pattern recognition and evaluation. These are the primary functions of the mind. We need to be able to dice up the environment to understand its parts and how they fit together, and we need to place values on these elements by figuring how they affect us. Where does reason stand in this? It's the ability for us to put together the pieces. It's the side that allows us to recognize the parts for what they are, to understand how they join together, and to perceive cause and effect. This is not the same as evaluating, which is based on subjective interpretations of what is good. What's important and desirable is obviously going to be different for you than for me. We can reason that an international confrontation of some kind, like a nuclear war, will cause the annihilation of the human species without making any value judgments as to whether or not that's a bad thing. Cockroaches would probably find a post-apocalyptic world awesome, and if they figure out how to create a false-flag event that will get us into a spat with Russia, then we are doomed. It is only because we value the human race, and the Cheetos factories it operates for our benefit, that we find the idea of an irradiated chaos to be problematic. For some hardy people, it still might be preferable, and for environmentalists, about the only thing standing in the way of them saying that we need to kill a couple billion right now for society to be long-term viable is the threat of looking like assholes as they try to sell an unattractive lifestyle.
So you have this cause-and-effect, calculator-style faculty of the mind, and the evaluating part of the mind. Logic, in normal use, seems to be the name for the first faculty. But what many people call "reason" is a form of logically connected value judgment, ethics with no objectivity to them in the Western tradition but in which systems of thought can be made internally consistent. This internal consistency is not based on anything outside of the mind; it is the prevailing interpretation of value judgment in society, by no means relevant beyond the individual or cultural worldview of whoever is developing that system. But because Western logic dominates the marketplace of ideas in our society, it has been portrayed as "reasonable" in ways which it clearly should not if we base the standards on observed phenomena in objective reality. There is, quite simply, always bias in these systems, because they start out with givens as presented by the Western intellectual worldview.
In John Rawls' A Theory of Justice, Rawls referred to people as both "rational" and "reasonable". Being rational meant that we wanted things we presumed could exist and assumes economic self-interest, obvious enough in observed human behavior. Being reasonable meant something with much more philosophical punch: to be reasonable was to say that people were willing to achieve those ends cooperatively. There are two things to gather from this. First, Rawls takes empathy to be a normal human emotion, and seems to believe that it is not normal to distribute it unevenly. It is a flat-out rejection of the notion that people view each other through an instrumental lens instead of an empathetic one. The other is that authority has little value from this perspective, fulfilling the goal of organization for utilitarian benefit and nothing more.
The other example is from Harvard (correction, Princeton) philosopher Robert Wright, who stated a similar worldview in his book The Evolution of God, but with less obfuscation as to what he was actually trying to communicate. At the end of the book, having made an interesting case as to the economic background and benefits of religion, Wright says that religion was valuable for humanity in "waking people up" to the reality of other peoples' right to exist and pursue their individual interests, and in the realization of a moral order. But while some people will continue to want some sort of faith for personal reasons, it's no longer necessary for civilization, probably harmful for inter-group cooperation, and often dangerous. Wright's work is related to that of the New Atheists' work in looking at religion as creating irrational aberrations to cause-and-effect processes.
It should be noted that Wright has also dedicated an entire book, Non-Zero, to the notion that human existence is not a zero-sum game and that our collective rational understanding of this is imminent. He assumes self-interest, he knows the importance of worldview, but he sees the worldview that disagrees with his understanding of the world as being obsolete or harmful and easily discarded to create a better world. What a surprise. Wright barely touches on hierarchy and legitimacy in either book, and his view of the human as a thinking being who mysteriously places equal and infinite value on others for some greater reason than self-interest stands as representative for Western thought.
The Original Purpose
Rawls also suggested in A Theory of Justice that morality should be viewed from a perspective of, essentially, a disembodied mind unaware of its own gender, race, beliefs, and socioeconomic status; he called this the "original position". Now, never mind that almost every respectable social scientist will say that our thought is shaped by things like our beliefs and socioeconomic status, which makes thought from outside our perspective extremely vulnerable to ridiculous biases. What matters is, Rawls assumed a sense of universal empathy sensible only to Westerners trained in the Judeo-Christian moral tradition; his way of thinking, which gave foundation to arguments which undercut the validity of all hierarchies not purely functional, described life purely in terms of individual opportunities. It's tremendously popular among liberals.
I would prefer a different way of thinking less focused on this conveniently altruistic individualism. I'm suggesting an "original purpose" to reason that might inform us of its value, and its limitations. What is reason for? What is its evolutionary purpose?
I think you can see where I'm going with this; reason exists for power. And only for power. The original position is irrational; reason is always purpose-driven; it is never all-knowing, all-encompassing enough to describe anything resembling the complexity of reality. Only a hypothetical God could have such a perspective. We can try to teach people to think broadly, but it becomes clear after a while that people continue to look out for number one, and stand up for those they identify most strongly with in cases of conflict. All rationality is bounded rationality, and in the arguments over decision-making and moral behavior, it works much more like Jonathan Haidt said in The Righteous Mind; as a political spokesman for our self-interest.
Seriously. Lots of people might look to science and say, "well, this isn't about power." Really? Science doesn't exist for the purpose of empowering the society which values it? So when we try to become more technologically advanced, we aren't trying to manipulate our world to serve our interests? When we build a telescope, is its purpose to allow people to look through it and say, "hey, cool!"? Do we not want credit, appreciation, maybe even to make a handsome living for making it possible? Is research not done with some ends in mind beyond adding to the repository of Western knowledge for its own sake?
An Evolutionary Faculty
Part of the problem here is that this perspective is so obvious. It's the perspective of seeking success. In fact, some people might see it as just saying that people are economically rational and self-interested. There is certainly a good case for economic thought being rational; our attitudes evolved to operate in this way. I mean that literally. Attitudes evolved, mental skills evolved, and the attitude we know as being 'reasonable' is a product of evolution. Go find a biology website and read the descriptions of the creatures and their adaptations. You know what you're going to find: Porcupines with quills, fish with camouflage, geckos and frogs with amazing tongues, adaptations galore. Hunters are well-equipped to attack, prey well-equipped to escape, social creatures well-equipped to live within their respective social structures, but also to thrive in them. This looks so reasonable, for all of this to develop, despite the fact that it's all the product of a process lacking in moral consciousness. It's actually extremely bloody and brutal. That's because evolution rewards power, and we're attuned to power. Knowledge and understanding are products of reason, but reason exists to seek power. The mind is a machine that can circumvent normal evolutionary processes by allowing us to understand and adapt our behavior without needing to be genetically culled, for the sake of greater empowerment. And man, does it ever work. It relies on evaluation, on recognizing the value of what surrounds us, and there is no sense to believing that people don't look at each other in this way as well. We view each other as unequal, which is completely and totally rational. To view people as equal is the irrational idea.
Now, look at what Rawls and Wright were calling "reason" through this lens. Are they practicing truly disembodied, neutral thought, which looks at everyone's perspective as equal? Or is the process of popular reason a tool for pushing a perspective, expanding your cultural identity, while discrediting competing views?
As a matter of breaking down the mechanics of a system, reason has utility for the user. But in a complex system, inherently unstable and dynamic, sophisticated enough to adapt, it cannot be predictive to any significant degree. The field with the highest degree of predictive power in the social sciences - economics - is inherently cynical in its view of human nature; still, it fails to predict anything with greater accuracy than your local meteorologist. When it comes to changing that system to more closely meet one perspective on progress, reason often turns out to be a mess. It's easy to forget that academic reason is a discourse, a dialectic, meant to bring about consensus, a manipulative discussion. You convince, and truth is a secondary matter to effectiveness by nature. If people really understood how little difference there is today between education and propaganda, we might find it easier to understand why Christian parents want their children going to parochial schools instead of viciously secular public ones.
The New Church
In The Evolution of God, Robert Wright talks about a "conformist bias" in people, which he relates to both the survival of religion and Stockholm Syndrome. People believe what their surrounding crowd believes; it's a straightforward case of reinforcement, where you gain acceptance through adopting the traits, the identity, of your group. Now, this is obviously a convenient adaptation, although Wright seems quite happy to mention that it can only exist in the case of there being no optional beliefs to choose from. But I'm not sure how aware people are that they continue to conform in the necessary manner with humanity's opinion on reason.
Western values are convenient in some cases; they bind us into a similar worldview, those values are assumed to be true to everyone, and those values are also assumed to make the world a better place when broadly shared. Our legal system - actually very traditionalist - is based on those shared values. Now, if anyone who was actually viewing the species from a distance were to look at this situation, I think the obvious conclusion would be that Western reason has become a new religion itself, complete with faith that it will bring together the masses in a better world, a powerful and sneaky campaign to eradicate competing beliefs by dressing them up as irrational lifestyle choices, disgust for apostates who convert to that old-time religious irrationality, the desire to get everyone possible into religious institutions for indoctrination (it's called college), and the obvious placing of "reasoned" values above other ways of thinking. It has its heresies - witness political correctness - but the thing is, it lacks the will to really punish violators, because it insists that its purpose is to bring about a better world based on individual choice and freedom, and that the violence of earlier systems marked them out as inferior. Our over-developed sense of superiority to the past fuels such illusions. But we cannot do lab experiments to determine what constitutes truth in personal values; we can only play games and push our perspectives. So reasoning values will continue to be decided how they have always been decided, by people in respected, holy institutions using their power to gain consensus and spread their views. They will just be doing it from universities instead of churches, and they will take on the old job of justifying the hierarchy with false promises and exaggerated claims, only trying to use material satisfaction as the metric by which a good world will be identified.
This perspective is already well established and unquestioned. Reason is thrown around as the ultimate arbiter of correct action in ridiculous ways. How much of the gun control debate is defined by liberals asking, "what's the reason you need these?" Evidently, we must justify every action and preference through a reasoned/religious ideal. But it is enough for homosexuals to say, "because I want to" in justifying an attitude that takes sexuality to be far more important than ever before. This is as biased and ultimately arbitrary as any other system of religious thought. It makes no sense except as a very shallow and mindless way of justifying one's ideological preferences.
As always, we're stuck with a system of thought that looks more and more like different strains of a mass psychotic delusion, fighting each other for public opinion and political leverage. Every opinionated hack can look to the body of "reasoned" thought and find the correct chapter and verse to translate into a justification for whatever they want, vindicated by the scripture of thinkers as diverse as Dawkins, Marx, de Beauvoir, Friedman, and Zinn. Whoever's popular, really. There's something incredibly stupid about expecting a strong and stable ideology to form in such a mess, but that's exactly what a cultural ideology needs to be in order to create peace. Without it, no action will be legitimate or illegitimate, no expectations can be rationally held, and no sense of identity can be formed across the broad swaths of humanity perpetually grasping for control.
Academics know that man is the measure of all things - such is subjectivity - but evidently have failed to understand that man is an aggregate that is difficult to harmonize. When they figure out that the responsibility of the group in power is to create stability, a responsibility important for both themselves and for the people they dominate, then they are going to have a hard time justifying their own exercise of power. So you tell me; can this work? Can reason be what religion has been in the past, or create a more satisfying life out of the material world alone? Do you accept the necessity of submitting to the Church of Reason?
Of course not. You'll just use reason to justify your perspective. Why would you do anything different?