Cognitive distortion, where an opponent subconsciously seeks out and interprets information that supports their beliefs and ignores contradictory information. There are two main cognitive mechanisms (with a large number of additional ones, especially in negotiations) that explain the tendency to confirmation:
1) Problem avoidance. A person does not want to know that he is wrong. For example, if he believes deeply in a certain diet, he may ignore new research proving that it is ineffective.
2) Search for reinforcement. A person wants to know that he is right. For example, if someone believes that a particular teaching method is highly effective, they will pay more attention to the research that supports their point of view, ignoring those that show the shortcomings of the approach.