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The enemies of rational thought can take one of several overlapping forms, including formal fallacy and informal fallacy, cognitive bias, cognitive distortion, and self-deception. If these are difficult to define, they are even more difficult to distinguish.
Formal and Informal Fallacy
A fallacy is some kind of defect in an argument and may be either intentional (aimed at deceiving) or, more commonly, unintentional. A formal fallacy is an invalid type of argument. It is a deductive argument with an invalid form; for example: Some A are B. Some B are C. Therefore, some A are C. If you cannot see that this argument is invalid, complete A, B, and C with ‘insects’, ‘herbivores’, and ‘mammals’. Insects are clearly not mammals!
A formal fallacy is built into the structure of an argument and is invalid irrespective of the content of the argument. In contrast, an informal fallacy is one that can be identified only through an analysis of the content of the argument. Informal fallacies often turn on the misuse of language; for example, using a key term or phrase in an ambiguous way, with one meaning in one part of the argument and another meaning in another part (fallacy of equivocation). Informal fallacies can also distract from the weakness of an argument, or appeal to the emotions rather than to reason. Here are a few examples of informal fallacies:
- Of course he’s guilty: even his mother has turned her back on him. (Appeal to popularity)
- Some people are in favor of building a third runway at the existing airport, while others are in favor of building a brand new airport. The two parties ought to compromise by erecting a new terminal building at the existing airport. (Argument to moderation)
- Tim is useless and Bob is a drunk. So I’ll marry Jimmy. He’s the right man for me. (Damning the alternatives)
- Despite their best efforts, scientists have never found any evidence of current or past life on Mars. So we can be pretty sure that there has never been any life on Mars. (Argument from ignorance)
Self-Deception
As I argue in Hide and Seek, all self-deception can be understood in terms of ego defense. In psychoanalytic theory, an ego defence is one of several unconscious processes that we deploy to diffuse the fear and anxiety that arise when we who we truly are (our unconscious ‘id’) comes into conflict with who we think we are or who we think we should be (our conscious ‘superego’). For example, a person who buys a $10,000 watch instead of a $1,000 watch because “you can really tell the difference in quality” is not only hiding his (unrecognized) craving to be loved, but also disguising it as an ego-enhancing virtue, namely, a concern for quality. Whereas formal and informal fallacies are more about faulty reasoning, self-deception is more about hiding from, or protecting, oneself.
Cognitive Bias
Cognitive bias is sloppy, although not necessarily faulty, reasoning: a mental shortcut or heuristic intended to spare us time, effort, or discomfort, often while reinforcing our self-image or worldview, but at the cost of accuracy or reliability. For example, in explaining the behavior of other people, our tendency is to overestimate the role of character traits over situational factors—a bias, called the correspondence bias or attribution effect, that goes into reverse when it comes to explaining our own behavior. So, if Charlotte fails to mow the lawn, I indict her with forgetfulness, laziness, or spite; but if I don't mow the lawn, I excuse myself on the grounds of busyness, tiredness, or bad weather. Another important cognitive bias is confirmation, or my-side, bias, which is the propensity to search for or recall only those facts and arguments that are in keeping with our pre-existing beliefs while filtering out those that conflict with them—which, especially on social media, can lead us to inhabit a so-called echo chamber.
Cognitive Distortion
Cognitive distortion is a concept from cognitive-behavioral therapy, developed by psychiatrist Aaron Beck in the 1960s and used in the treatment of depression and other mental disorders. Cognitive distortion involves interpreting events and situations so that they conform to and reinforce our outlook or frame of mind, typically on the basis of very scant or partial evidence, or even no evidence at all. Common cognitive distortions in depression include selective abstraction and catastrophic thinking. Selective abstraction is to focus on a single negative event or condition to the exclusion of other, more positive ones, for example, “My partner hates me. He gave me an annoyed look three days ago (even though he spends all his spare time with me).” Catastrophic thinking exaggerates the consequences of an event or situation, for example, “The pain in my knee is getting worse. When I’m reduced to a wheelchair, I won’t be able to go to work and pay the mortgage. So, I’ll end up losing my house and dying in the street.” Cognitive distortions can give rise to a chicken-and-egg situation: the cognitive distortions feed into the depression, which in turn feeds into the cognitive distortions. Cognitive distortion as broadly understood is not limited to depression and other mental disorders, but is also a feature of, among others, poor self-esteem, jealousy, and marital or relationship conflict.
Read more in Hypersanity: Thinking Beyond Thinking.
