Passion clouds reason
Hate, greed, envy, lust, wrath, arrogance, etc., are negative feelings that can easily become passions. In general, passions cloud intelligence, even good passions, but even more so the bad ones. The case of Balaam is very instructive.
Two passions had taken power over Balaam; the first one was greed and then wrath. His understanding was so clouded by the passion (wrath), that it impeded him to detect the fact that his donkey was speaking with him. The case in which a donkey speaks is so unusual that from the moment in which the donkey asked "what have I done", Balaam surprised and even frightened should have deposed his attitude. But his irate passion was so immense that it dominated his intellect, and he began to argue with the donkey without noticing the he was witnessing a miracle.
"28 And the LORD opened the mouth of the ass, and she said unto Balaam: What have I done unto thee, that thou hast smitten me these three times? 29 And Balaam said unto the ass: Because thou hast mocked me: I would there were a sword in mine hand, for now would I kill thee. 30 And the ass said unto Balaam: Am not I thine ass, upon which thou hast ridden ever since I was thine unto this day? was I ever wont to do so unto thee? And he said, Nay." (Numbers 22:28-30)
Passions (arrogance, vanity, pride, fear, holding a grudge, envy, greed, etc.) blind the understanding of man. Every time I have argued with someone who refuses to understand clear arguments, that are clearly exposed, I have been able to see interposed between us, one or more passions on the part of my interlocutor. I have been unfortunate enough to have spoken with many donkeys, who are as such, because they give in to their passions. And if these donkeys speak without any a miracle, it requires a true miracle to make them reason.
Another biblical case in which one or more passions cloud intelligence is that of the priests and the resurrection of Lazarus.
It has been my observation for many years (decades) that when some type of feeling is mixed in with an analysis of something, man cannot apply logic and reason or he does so partially. This difficulty becomes bigger as the feelings become stronger, and becomes a crisis when that feeling becomes a passion and that passion is disorganized and does not come to a standstill.
That was the case in the princes for the priests in this passage. Their passion was hatred; because of the fear they felt that Jesus Christ would displace them from their preeminent priestly position. Their hatred was such that instead of trying to reason that whoever had raised Lazarus had to have come from God, what they try to do is kill Lazarus, because this constituted the living proof that they were wrong in not accepting Jesus as their Messiah.
"9 Much people of the Jews therefore knew that he was there: and they came not for Jesus' sake only, but that they might see Lazarus also, whom he had raised from the dead. 10 But the chief priests consulted that they might put Lazarus also to death; 11 Because that by reason of him many of the Jews went away, and believed on Jesus." (John 12:9-11)
Anyone could believe this total collapse of reason is impossible, but would not think the same if as myself, have observed completely how a person's ability to reason is atrophied by simply not having used his sense of reason for years. I have met some people who only reason with logic in their daily activities, in their profession or trade, where they have been trained to reason before their passions took power over them.
I have met some that due to mental laziness have atrophied that beautiful human ability to the point of not being able to use it in anything that is not what already constitutes a beaten path in the nervous system. A path not caused by conscious reactions but by defensive reflexes to the survival in society.
Examples of this are the capability to make businesses, to lie, to flatter and obtain what they want, to conquer the opposite sex, to work in their profession, etc.. They are incredibly sharp in a determined type of activity related with that type of surviving in society that they have chosen; and are at the same time, incredibly incapable of reasoning in any other sense.
Perhaps the explanation to this inconsistent polarization of the use of reason can be that they were trained to reason without giving in to their passions only in a particular activity, when they were children or young adults. It could also be explained in the respect that they were instructed to accept in a dogmatic manner the premise of their profession or particular activity. To their benefit, these premises are real and from that point on, with a rudimentary process of reasoning, they can reach certain correct conclusions. Even more so because in the majority of cases, it was instilled in them at a very young age, to use reason in a mechanical way when it came to the aforementioned premises.
It is not that they cannot reason, it is that they quit using that power, that ability, because it leads them to undesirable conclusions, and they prefer to refuge their mind in the use of instinct and / or the process of conditioned reasoning, which exist as much as conditioned reflexes (learned reflexes).
The types of feelings and passions that cloud reason are many: self preservation instinct, pride, arrogance, hatred, frustration, envy, selfishness, wrath, an obsessive love towards someone or something, complex of superiority, passion for fame, self-worshiping, etc.. All of those can be condensed in two primary or fundamental causes: either there is no love for God above all things, or there is no love for others as we love ourselves, or both.
Upon failure of these, there is such an exaggerate love for his son in comparison to the neighbor's, that a human being cannot see that his own son may not be right. The contrary is also true, because of the love you have for yourself, you fear the confrontation with the father of the other child who accuses yours, and cannot see or does not want to see that your child is truly right.
The masses, full of envy, hate a wealthy man even though they know nothing about him; they agree with those who attack him even if they do not know the facts. The egotistical rich man cannot understand the resistance of the poor when it comes to his whim. "Do you not see who you are?" thinks the important person in relation to someone of lesser social standing. They truly believe they are in their right to enjoy excessive riches at the price of the hunger of others. "The poor are accustomed to that life and do not need to leave it", is the thinking, while they take advantage of those beneath them. Greed, pride and other passions do not allow them to see that they are on the border of a precipice of a social commotion, and therefore in the end, will suffer it.
If those who possess a clouded intelligence because of their passions would allow us to take them through the process of reasoning to ultimate consequences, they would see themselves without justification. That is why they avoid it. That is why they do not accept discussing their opinions brandishing diverse "noble" pretexts. By way of a subconscious defensive mechanism, they maintain the process of reasoning in the most superficial layer of the mind.
In these superficial layers of reasoning they have already constructed a platform of reasoning that is auto-justificatory. That auto-justificatory platform could have an internal logical consistency, but be based on a false premise, or in a sublevel reasoning platform without internal logical consistency. Additionally, it may be that this particular sub-level is logical, but may be based upon a second sub-level, which is the one that may have not consistent internal logic or is based on false premises or both.
In persons that are more intelligent or more complex, sometimes we have to look to a third or fourth level in order to arrive at the origin of their error or to find the falsehood behind which they hide their wickedness. It is, at times very very deep where we discover the false premise from which they part or the false step in the chain of reasoning, the broken link which make a chain useless. That is why they justify themselves with their words, but don't allow anyone to take the discussion or reasoning deep enough to discover the deceitfulness of their apparent honesty or justice
While more sub-layers of reasoning separate the discussed error of the sub-platform without internal logical consistency, or of the erroneous premise which sustains it, the harder it will be for the one who is searching for the truth, to find it. Also, it will be "most impossible" to demonstrate what their error is, especially in those who do not wish to find the truth because it is painful.
The princes of the priest could not reason that Christ had to be the Messiah; they could not reason that it was to their advantage to be with the Messiah; their passions: pride, vanity, hatred, egocentricity, etc., hindered it. This happens to rebel angels as well.