That is, the confiscation of a normal reasoning process to serve an evil end.
Why do people deny things like evolution, peak oil, global warming, taxes? Why are they able to rationalize these things away so easily? Why are they so capable of concluding that obscene profits are morally OK?
When someone can't deal with reality as it is, they often turn to rationalization to support their beliefs, say in an ideologically-based fantasy. That is, they are subconsciously motivated to stick with their belief system and find a way to argue that their beliefs are right and that the situation they find themselves in is completely consistent with those beliefs. When they do so they are working backward from the facts on the ground to look for ways in which their a priori beliefs can explain the situation. Often times the mind can find the most ingenious ways to reconcile its beliefs with the facts. The more out-to-lunch those beliefs are, the more torturous the logic that makes it all right and brings some comfort to the individual. I would have to say the most extreme of these has to be the religiously dogmatic believers (e.g. young earthers, etc.) and the libertarians or neocons. For them, everything is derivable from their ideological stance.
It turns out that the process of reasoning that is used in rationalization is just the subversion of a very normal process that the brain does all the time. It is called abduction.
The word abduction has several meanings. The obvious and most widely known one has to do with absconding with someone against their will. The lesser known one has to do with a form of reasoning or inference. From Wikipedia:
Abduction, or inference to the best explanation, is a method of reasoning in which one chooses the hypothesis that would, if true, best explain the relevant evidence. Abductive reasoning starts from a set of accepted facts and infers their most likely, or best, explanations. The term abduction is also sometimes used to just mean the generation of hypotheses to explain observations or conclusions, but the former definition is more common both in philosophy and computing.
In other words, abduction is a form of backward inference. Starting with observations of the state of the world, one reasons backwards from effect to probable cause. This can require a chain of inferences in which one seeks a more distal cause such as happens when diagnosing a medical condition. One starts with symptoms and works from there to determine the most likely disease. In the case of environmental factors (e.g. pollution) one might need to look further back to determine what caused the disease.
Abduction is something we do all the time. It is our reasoning method for providing explanations for what we find to be true. It only works if we have constructed very good models in our minds of how things work so we can use those models to work backward and explain why things are now the way they are.
Abduction differs from the other two main forms of reasoning or inference processes, induction and deduction. The former is used to arrive at generalizations after observing a set of specific instances that all have a common set of features. For example after a child sees three or four dogs that have fur, she might infer that all dogs have fur. This is a form of learning and abstraction of an ideal from similarly featured experiences. It is, in fact, how we build conceptual models from our experiences. Inductive reasoning is not guaranteed to be correct. For example after concluding that all dogs must be furry, suppose the child encounters a hairless chihuahua? Clearly the model needs to be amended to 'most' dogs are furry. Induction is related to stochastic learning where relative frequencies of feature association are used to build up fuzzy models.
Deduction is the other form of logical inference, and probably the best known. Sherlock Holmes would often tell Dr. Watson that his method was simple deduction. In fact Holmes never or rarely used true deduction. This is when you start from general truths and work out particular instances. So in a sense it is the opposite of induction. But it is more than that. If followed rigorously, deduction is guaranteed to produce a provable true answer!
Abduction is not guaranteed to prove anything. It is more generally a best guess of what happened in the recent past to produce the current situation. It relies on models built up from inductive processes in the past and so it could produce false results. But if the models one possesses are based on valid facts and relations, then the likelihood of abduction producing valid results is higher. That is why it is a valuable reasoning tool that has been the basis of our species success in evolutionary terms.
Only, when your models are based on suppositions and false beliefs, your conclusions are not likely to be valid. Rationalization is abduction subverted to produce what might be called a forgone conclusion. In our modern world of information overload, speed, change, opaqueness, and complexity is it really surprising that so many people turn to rationalization of comfortable, if misguided, beliefs? Isn't it easier to let someone else, someone who claims authority, give you your models of how things work? Isn't it easier to use mangled abduction to produce a conclusion that fits than to ask hard questions? How did the huge variety of plants and animals come about? That's easy. God did it.