A lie is best hidden between two truths.
Nothing can give more feeling of conviction to a wrong idea than to have it sandwiched with a couple of unidentified good ones.
One might look at a person who is blind to facts and to anything that does not confirm some belief of his and conclude that "One must have an open mind", which means, "one must listen to every Bullshit out there and never assert any full confidence in one's own opinion".
The true problem with the stubbornly blind is that they are stubbornly blind - that they do not conform to facts and truth, NOT that they are loyal to their own way and view.
There is a tendency not to distinguish between the different elements, to clamp them together, and then use one of them as the "core guideline", sandwiched in the power of the emotional conviction of the other truths surrounding it.
In this case, unwillingness to listen to others who disagree is what's being targeted - it is the lie that is hidden and reinforced by 2 truths, the truths being that it is bad to be willfully blind, it is bad to ignore people when they present relevant facts.
Consider a few other examples in which the true element explaining some bad behavior remains unidentified and some other good element is made to curry the guilt.
Take for example the following case:
A military-trained sniper decides to take the law into his own hands and execute people whom he believes deserves punishment without a trial. He also kills those who stand in his way and any law-enforcers who try to stop him.
There are many things that can be said about his behavior: He stands on his own, he has a strict moral code he is certain of, he is extreme in doing what he thinks is right, he is more focused on punishing the evil than protecting the good and more.
There are a lot of elements in his behavior that under a different context are admirable and yet in this case they all yield a bad result. If one is unable to determine what is the root of the evil in what this man is doing, one might easily warn oneself against one of those other traits that are good.
One might tell oneself something like: "See? this is what standing above other men will do to you", "See? being extreme can turn a man into a cold blooded killer. It is much better never to be certain of something when it comes to moral issues", or "This is what happens when a man stops listening to other people. One should always come to agree with others before acting on one's own".
The real problem in this sniper's behavior is that he is focused on punishing evil at the expense of hurting the good. If justice is his goal, he does not serve it. He chooses an illogical way to live in society (assuming the legal system is not corrupt - that would be a different discussion).
It is not easy to identify that element among all the rest, but if one does not take the time to do so, one might end up with a conclusion which would be devastating to one's life.
One might become afraid to make decisions on one's own, or do what one thinks is right, or stand alone in disagreement with others or even develop one's own moral code and stick by it.
If a crazy sniper that kills good guys is what happens when one is certain one is right, maybe it's better never to try to be right or do the right thing at all. The conclusion is a spiritual death sentence.
Another example of a lie hidden between "two truths" is the concept of selfishness.
We all know the type of people who seem to think "only of themselves" - they exploit others, do not respect their property or sovereignty and basically see people as tools for their pleasure or goals rather than real people with goals of their own and values.
Then, people confuse that with EVERY form of selfishness. They think THIS is what selfishness IS.
So actions like, making an honest living and wanting to keep the money for oneself, is all of a sudden bad, because one "only thinks of oneself" in doing so. Or wanting to take a vacation in Disneyland instead of giving the money to someone who needs food is "selfish".
Notice, however, that there is a big difference between exploiting someone else for one's own pleasure and simply making an honest living and enjoying it, but this concept of selfishness makes no distinction between the two.
The real problem with those who exploit others or see them as nothing more than a tool is a failure to see other human beings for what they are: human beings with goals and values of their own. It is a psychological problem and it actually makes the one who has it psychologically injured because they can never form intimate relationships and can never enjoy other people.
This element is much harder to identify, but it is the right one, and not identifying it can lead to devastating results, such as feeling guilty for wanting to enjoy one's property, life and money instead of giving it away.
Another example is a wrong conclusion about sex. One might look at a promiscuous person and conclude that sex in itself is wrong. The true element which makes the behavior wrong, is something else. There could be several reasons I can think of why someone would be promiscuous: they are afraid of bonding with someone deeply and so they project their fantasies on strangers, they have low self esteem and are trying to bring it up by getting sexual attention from others and so on.
The true element is harder to identify, but a conclusion like "sex is bad" or "it is bad to be attracted to many people" are wrong and damaging. For teenagers especially, because as a teenager, it's not as easy to identify one's values in others and so it is normal to be attracted to more people than one's adult version would.
Another example is the notion that caring about one's external appearance is "superficial" and bad. It's ground in reality is people that appear to have "no personality" and only care about their appearance, or people who preserve their appearance as a replacement of good character.
A.K.A the Beverley hills bitch who would be caught dead wearing the wrong item but would destroy someone else's hopes without a moment's hesitation.
One might look at her and conclude that somehow caring a lot for one's appearance is tied with being evil. This can lead to giving up on a great pleasure: On looking good and celebrating one's own value in social settings.
Similarly, one might look at a narcissist and conclude that self-love is bad. Or at least "excessive self love". Well, how would one measure something like that? It can't be done.
Narcissism has its root in something entirely different.
One does not have to identify the truth in all of those cases. One does not have to become a trained psychologist in order to avoid the problem of condemning self-love.
However, it is sometimes hard to leave some case one observes without drawing some conclusion from it. In fact, one might conclude from this blog post the conclusion that it is best never to draw conclusions from cases one sees.
I think the correct course of action is either to take the time to completely figure out what is the root and cause of some bad behavior you see, or just to tell yourself that you have no way to determine that and simply walk away without a conclusion.
What one ought to watch out for are those snappy conclusions one makes based on superficial observations (like looking at the pretty bitch and conclude that caring for your looks is bad).