Worldview Building

I'm not a psychologist, just an average people watcher. But I'd like to talk about the things that create a person's worldview. This is mostly for authors to craft more realistic characters. I'll give some real world examples and allow you to think how your characters would be affected in their particular worlds.

The First Impression
Perhaps the most important, and certainly the most fundamental, determinant in defining worldview is the first impression. I've found that the first impression is the hardest to erase, even when presented with contradicting evidence. That's not to say it can't be done. In fact, we have some very good instruments in our toolbox.

Betrayal
Perhaps one of the most effective tools in erasing the first impression is betrayal. It may take ten times, it may only take once. Even when the betrayal turns out to be an unfounded rumor, the new impression remains stamped over the first impression. Sometimes the distortion of worldview occurs in interpersonal relationships, and sometimes it happens on a larger plane, for example with religion. E.g. "I didn't know that [historical religious figure] did [action]. Why didn't anybody tell me?"

Superciliousness
Also known as haughty disdain or arrogance. Betrayal is often, but not always, the overture to disdain. It's the feeling that "I have secret knowledge and am therefore better," or "anyone who doesn't realize what I do is mentally inferior." It can also be derived from advantage of physical/monetary circumstance, but I've found for the average person it's knowledge-based. These feelings are often gleaned from reading/hearing language laced with the following fallacies: argument by emotive language, appeal to spite, alleged certainty, cherry picking, definist fallacy, historian's fallacy, is-should fallacy (naturalistic), political correctness fallacy, overwhelming exception, proving non-existence (burden of proof), and many others.

Repetition
I think we all know it's a logical fallacy, but that doesn't stop us from falling for it. Argument by repetition, or argumentum ad nauseum, is the act of repeating a premise over and over to bolster its veracity. A fantastic example is, "Fat is attractive." We're hearing this argument more and more (and more and more ad nauseum) until we reach the point that we start to think, "Wow, I don't think fat people are attractive. Maybe there's something wrong with me." Taking a step back and assessing the situation, it's easy to see that ignoring millions of years of evolution to validate aversion to self improvement is unsound and not those who aren't romantically attracted to obesity.

Shaming/Humiliation
Often accompanying argument by repetition is argumentum ad verecundiam, appeal to shame, closely overlapping strawman fallacy, appeal to emotion, and argumentum ad hominem. Let's take our fat attraction example. Society wants to thresh us with shame if we don't experience romantic attraction to obesity, thereby trying to short-circuit our brains and remove us from a logical, biological context and thrust us into an emotional, irrational context. This is often accomplished by setting up the defending party's views as a strawman (a grotesque misrepresentation) and then trouncing it. They shame you by telling you that you're shaming them.

Conclusion
In conclusion, there are many other things that influence worldview, but I think these are some of the strongest points. For example, aphorisms and proverbs can change worldviews, but how often do you think the people reposting maxims on Facebook actually apply them to their lives? To craft more realistic, flawed characters, I encourage you to study logical fallacies and program some of them into your characters' worldviews. Challenging a character's worldview is easy and compelling conflict. I'll close with one that I really like, the sunk-cost fallacy. It's the erroneous assumption that since you've already invested so much in a project/idea you have to see it through to the end.

Edit: I might add more as I think of them, but another important one I thought of is Indignation, or more specifically indignation affirmation. This isn't so much a change in worldview as it is a deepening of one's current view. It occurs when someone takes offense at an opposing worldview and then invests more emotion into their own. This reeks of the sunk-cost fallacy and self-imposed appeal to emotion, but we all do it.

Bonus fallacy: Argumentum ad Homonym - when you try and use there instead of their.