It is not merely religious people that can be stubbornly stuck in their beliefs. Facts, figures, and even empirical evidence can sometimes be dismissed by the most critical of thinkers due to everyone's distaste for being wrong.
Kathryn Schulz, a journalist who is often noted as starting the new field of study dubbed "wrongology," has pointed out that humans will do just about anything to avoid being proven wrong. We are taught from childhood onward that being incorrect, being wrong makes us a "failure." Mix that with religions that teach that doctrines must be accepted with faith-like credulity, these religious adherents will equate being "wrong" with being "bad," being "unfaithful to God." No one who believes in a deity that they've chosen to worship wants to think of themselves as "unfaithful" to their god.
Again, this isn't limited to the religious. Anyone can suffer from what wrongologists call "error blindness." This is the denial that one is wrong or can even be wrong. Scientists have been known to ignore evidence and even sabotage the work of other scientists who may be disproving their own views or see another's work as challenging their own theories. People tend not to embrace the idea that being mistaken is human. We rend to forget that we are always capable of being in error at any time about anything.
To demonstrate that this can happen to even unreligious people, though the above information linking the Canaanite deity El to the Jewish God is popular on the Internet, it is also not very correct. I'm Jewish, an instructor on critical Hebrew philology, and I see this mistake all the time.
The link between the the Canaanite El and the Jewish God appears to work on the surface, but is an etymological anachronism. Both deities were worshipped during the same periods, and it was common for Semitic language to share words, using EL or forms thereof to refer to deities and grand storms. For instance, another word that was commonly shared by Semitic communities for deities was BA'AL, and not only is the Hebrew God referred to as BA'AL in Scripture, the Hebrews named their children employing this name of God as in Jerubbaal, Ishbaal, and Meribaal.
Aramaic, Phoenician, Ugartic, Hebrew, Syriac, etc., shared similar words for deities much as Latin, French, Spanish and Italian share similar words for similar things. The connections between the deities, however, can't be made from this shared vocabulary. The Canaanite El, for instance, was a rival to El of the Hebrews as they were worshipped around the same time in the same area.
Also, the concept of God shared by my people the Jews is quite the opposite of what most non-Jewish readers of Scripture understand. For Jews, "God" is actually not a god. In very basic terms, the concept of "God" for us Hebrews is that there is no such thing as gods, that all deities are false and subsequently all religions are a waste of time. As Jewish tradition, the Mishnah, and the Talmud state, "God" is the great "Cause" of all that we witness in the physical universe. "God" may actually be the universe, or greater than the universe, some Jews hold. Above all, Jews for millennia have seen "God" are transcendent of understanding, mysterious beyond our learning, incapable of conceptualizing, escaping definition. The ancient story of Abraham destroying his father's collection of idol gods upon realizing this concept of the "Great Cause" has led one Jewish teacher I know to refer to God as the "un-God."
This is why some Jews are atheists, others agnostics, some humanists, and others even Buddhist (which has no god at its center). These Jewish "atheists" will still observe Shabbat and pray the Shema, celebrate Chanukah, and observe Passover, leading the prayer and chanting during the Seder. Belief in a god or deities is not required of Jews because of this unique monotheism we possess in our culture.
Despite the etymological and philological evidence for this (which can be found by going to Jewish resources), most proponents of the "EL is YAHWEH" argument have not only failed to dip into Jewish studies on the subject, most have never asked a Jew (or believe them) when the subject arises.
I am not the only one who has attempted to discuss this with persons who hold this "EL is YAHWEH" view as "truth," and I am surely not to be the last, but many of these have "error blindness," not seeing what a mistake it is not to apply the scientific method rule of having your conclusions verified by several disinterested parties. A lot still fall into the old Watchtower trap of singing the old "I did the research myself, and now I know the truth" song, and can be quite nasty when you try to demonstrate that just failing to go to Jewish sources or walk into their local synagogue or temple and ask someone about this is quite a mistake.
Wrongology teaches that it is "error blindness" to believe that there are "beliefs" that cause people to be "mentally lazy, dishonest, cowards and foolish." In reality, we need to face the fact that we are all prone to acting the same when it comes to acknowledging we might be in error. It isn't intelligence that is lacking when people get "error blindness." It's often the understanding that we are all prone to be in error, and that it is not only human to err, it is also human to claim we haven't.