Ignorance, on the other hand, usually indicates stupidity in that important data are present and gatherable but unheeded. The reason that ignorance does not always indicate stupidity is that some information could seriously disrupt existing psycho/social systems were it to penetrate the cognitive defenses, so exclusion may sometimes be somewhat adaptive. This is really a rather complex process, as stimuli must be at least superficially perceived before being rejected by the system as being threatening to the existing belief structure or "Schema". Thus, motivation can play a role in ignorance if some relevant, available information is prevented from getting "Into the system" (i.e., accepted and incorporated into the cognitive program). This is likely to occur when a person senses that learning more about a particular matter might force him to undergo the most traumatic, terrifying experience one can be called upon to endure—he might have to change his mind.

It might be assumed that "Knowing is good", that there could not possibly be too much knowledge and that an excess of information could not possibly be unhealthy. However, people must compromise on both the quantity and quality of their information. In terms of quantity, people limit themselves by specializing—sacrificing breadth for depth, with each doing well if he knows something about anything. In terms of quality of information, people debase themselves by qualifying their standards—sacrificing validity for appeal, with each accepting whatever is suitable.

Unfortunately, these compromises not only fail to protect people from an overload of trivia but can keep them from knowing what is going on in their world. A given system can process only so much information so fast, and that should (theoretically) be important material, not insignificant detail. However, important material is not always brought to conscious light. At all levels, there is a secret aspect to human life—things which people do, although most of us should not know.

At the national level, every government has its covert band of operatives who skulk around doing whatever is necessary and improper. The general population and even most government employees are better off not knowing what is going on because the CIA, KGB and James Bonds are set up to betray the ideals which hold civilization together, so such important matters may be hidden from us.

At the individual level, too much candor can also be disastrous, as many doctors well know. There was a case of a terminal cancer patient who was given a useless drug (Krebiozen) and recovered.

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