On page 224 of OPAR Peikoff states “The mental practice that underlies the anti-effort attitude is the act of evasion, of blanking out some fact of reality which one dislikes. This act constitutes the essence of irrationality and, therefore, of evil.” I agree that evasion of a known fact is irrational and evil but I doubt it is the most common form. I believe what is more common is failing to make the effort to seek additional facts especially those which one suspects he/she may not like. In other words it is a type of self-imposed ignorance as opposed to suppressing knowledge you already have. For example, someone may believe in creative design rather than evolution. It is not that they know the facts supporting evolution but that they refuse to consider them.
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