Why do so many people - especially those in leadership positions - believe things that are false?
Of course, the ultimate reason for rampant falseness is dishonesty - since the world is ruled by evil, and evil always lies.
But proximately, how does it happen? What is the psychological mechanism by which so many people believe stuff that is contradicted at the personal level?... And also believe it to the extent of staking their own livelihood and lives on the truth of nonsense?
One important answer is committee consensus.
Although I hated and avoided committees throughout my 'career'; nonetheless I attended more than enough of them to recognize their cognitively-distorting effect.
This is a psychological aspect of committees which comes on top of their objective deficiencies as a decision-making method; and the destructive evils of voting to make decisions.
This is the way in which committees reach a consensus; which is then assumed to define reality.
I have seen this innumerable times. A committee has to decide on some-thing that is - or should be regarded - as a matter of fact; but the actual reason for a decision pushes facts down to the level of personal opinions; and personal opinions are framed in terms such as in-group versus out-group, people you like/ are powerful/ from whom we want favours - versus the opposite.
After a while, the members of the committee often reach a conviction of the rightness of... whatever-they-have-decided; and that rightness has nothing to do with the real world - and everything to do with that psychological state of conviction.
Then, on top, there is way in which committees integrate with the minutes and conclusions, the results and recommendations, of previous committees - such that the web of committee become the only valid reality.
In other words; the system of bureaucracy operates on the implicit and unconscious assumption that there is no reality out-with the system of bureaucracy - no reality with-which to compare and contrast the committee world.
And this assumption is all the more powerful for being implicit and unconscious (since it is so absurd that if examined explicitly it could not stand).
Yet consensus can be, and of course is, routinely engineered by well-understood techniques. Yet those who are thus manipulated nearly-always deny that it has happened... Probably because personal status and power (and employment) is conditional upon committee consensus.
At every level of modern society of which we are aware and in all major institutions; a committee stands at the apex of power. Therefore, there is no limit to the wrongness with which committees can - formally and officially - regard reality.
Now that we (in the West, especially) inhabit a totalitarian world - the web of committees is global, and links all social institutions within the nation.
Once that vast system has reached consensus on some-thing - there is a virtual reality of vast scale and complex inter-linkage to reinforce the virtual reality of consensus; there is no way-in for real-reality.
Indeed; there is no way even to acknowledge the separateness of real-reality; thus no way to compare real-reality with the virtuality of consensus.
Individuals have - en masse - made the choice that their own personal experience, reason, common sense are unreliable ways of knowing; and therefore need to be subordinated to committee consensus.
And, once that choice has been made; belief becomes something external to be obeyed - not something for which any individual is personally responsible.
And, once that 'something external' is a committee, functioning in a bureaucracy of their-committees - then we are in a world where committee consensus defines reality; and real-reality might as well not exist (without any regard of what yours or my personal judgment may say on the matter).
Consequently; it is possible, perhaps normal, that the things everybody believes in terms of public discourse; are things that individuals do not believe. Yet they have pre-decided that independent personal discernment ought to be suppressed; therefore they absolutely believe whatever nonsense is committee consensus. And such individuals cannot - in principle, under any circumstances - ever take responsibility to abandon that committee-derived consensus reality; because to do that would we be evil, and dangerous.