UPDATE: I have changed the title to the present one (from "Misinformation Theory") which I consider more appropriate. I have read a little bit on what others have had to say about this topic, but haven't seen my particular point in any readings. I followed the hint from Tom Paine's comment.
Information is now more available than it has ever been before, so are we better informed than we used to be? Well maybe. There are some problems.
For one thing, there are limits on the speed with which we can absorb information and the amount of information we can retain. For another, the same technology that permits rapid dissemination of information also permits rapid dissemination of misinformation. There is nothing new about deception, either. As a species we have always been good liars.
One of the oddest forms of deception is self-deception. It's pretty easy to see the possible evolutionary advantages of being able to deceive others, but what could be the percentage in fooling ourselves? This is especially interesting to me, since I think that it is a pervasive and frequently pernicious influence in life.
My guess is that the fundamental driver for self-deception is our need to achieve some kind of cognitive coherence. One of the things we do, or at least I do, is to try to build up a coherent picture of the world. The value of such a coherent picture is that it allows us to make logical deductions. It's well known in logic that anything whatsoever can be deduced from mutually contradictory premises, and that is a very real threat to our ability to reason about the world.
There is a social dimension to cognitive coherence as well. Our ability to cooperate with others is dependent on having a common understanding of the cooperative behavior - if we can't agree on goals and the nature of the cooperation, it can't happen. That fact, I suspect, is why societies go to considerable trouble to impose a common world view on their members.
New knowledge challenges and frequently overthrows old world views. Science is an ongoing challenge to our world view. The theory of evolution was one of the most fundamental challenges to the common world view ever encountered. Before Darwin, almost everybody believed in some version the intelligent design idea. A natural corrollary was that we all had assigned places in the designed universe, and that tampering with those places was an unnatural activity.
Natural selection challenged all that, and consequently challenged all established hierarchies and values. Most fundamentally, it challenged the necessity of a God to plan and order the universe. Religion quite naturally recognized a deadly enemy and fought back bitterly. That's the social dimension of self-deception in the sevice of cognitive consistency, but the individual dimension closely parallels it. If religion is a fundamental ordering principle for your world view, accepting natural selection creates strong cognitive dissonance.
An even more contemporary example is the debate over global warming. For those who see, it is a profound puzzle that others regard global warming as a political issue, but it is. The social dimension of doubt here is the clear financial interest of those who own polluting resources in suppressing a conclusion that would cost them money. The fact that doubters are overwhelmingly from the conservative ranks is in part a result of that social power and the propaganda it generates.
I don't think it is an adequate explanation, though. Plenty of doubters, some of them intelligent, have no clear self-interest in energy production and are too wily to be taken in by propaganda - unless it is propaganda that they want to hear.
Once again I think internal cognitive consistency is the root of self deception. If your fundamental world view is a mystical devotion to the ideas of individualism and the virtues of a free market, a happenstance that demands collective action is a very unwelcome visitor. This, I think, is the root of the conservative folly on the subject.
It is a fundamental insight of evolutionary theory that clearly disadvantageous traits like sickle cell anemia persist in a population because they have a side effect (like resistance to malaria) that gives them an evolutionary advantage. This sort of adaptation is a classic example of why intelligent design theories fail. My argument is that self-deception thrives as a side effect of the need to maintain cognitive coherence.
This post had its origins in a discussion of this article by Bee.