Mistakes in inference and attributing causality are common. Ignoring the law of large numbers is a prevalent error. While people generally understand the significance of having a representative sample size, there is a tendency to infer association or causality from a relatively few observations. The main reason for this is, of course, that life seldom presents statistically-sound sample sizes. Over time, people accept what they must, and may make more of it than they should. Further, everyone has experienced success despite the law of large numbers. Language learning is an exercise in generalization from a few examples.
Most people tend to ignore base-rate information (the typical), instead focusing on odd variations or unusual anecdotes. Besides the sample-size dilemma, it is natural that the norm is ignored while the unusual grabs the attention; but such is a poor basis for inference.
People tend to gather information before making judgments. As information is often unlimited, a decision has to be made as to when the data is sufficient to reach a conclusion. The decision to stop gathering data is influenced by whether the data points towards the desired conclusion.
People start with an assumption that their favored conclusion is more likely true and weight each piece of evidence supporting it more than evidence opposing it. Because of that, people will find no need to gather additional information that could have revealed their conclusion to be false. They will stop the investigation as soon as the jury tilts in their favor. ~ Dutch psychologist Filip Gesiarz
Confirmation bias is the tendency to interpret or prioritize information in a way that confirms a held hypothesis or belief; information to the contrary is shunned. A self-fulfilling prophecy is confirmation bias at work.
Confirmation bias leads to determining causality from correlational evidence alone, and illusory correlations. Cherished beliefs are especially prone to confirmation bias.
Confirmation bias can have a major effect on our everyday lives. ~ American psychologist Robert Sternberg
First impressions are often lasting impressions, and those first impressions often owe to expectation. The way we treat people when we first meet them greatly affects a first impression, as people interactively respond to how they are treated.
The tone of a first meeting, and hence a first impression, is often set beforehand, by what we have heard from others, or information otherwise obtained. Finding that we do not like someone we expect not to like can be confirmation bias, as we treat them less civilly than when our expectation runs to the affirmative, in which case our own cordiality can be contagious, and we again confirm expectation.
Causal analysis provides absolutely no value judgment, and a value judgment is absolutely not a causal explanation. ~ German sociologist Max Weber
If formal logic is to be treated as a model of competence, we need to know which logic or logics human beings have internalized, and the nature of their mental formulation. ~ American psychologist Philip Johnson-Laird