We all tend to be forgetful once in a while or have thoughts that are counterproductive. However in psychology there are several areas of human thought that have been identified as common faults.  My favorite is The Confirmation Bias, which I already knew to be true.

The confirmation bias is the tendency to look for or interpret information in a way that confirms beliefs. Individuals reinforce their ideas and attitudes by selectively collecting evidence or retrieving biased memories.

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