Perhaps it is because of weight of evidence for the other side as well, and your refusal to acknowledge that.

Nevertheless, it seems that our views often not held because of rational reasoning. I personally have found some of my own biases well grounded, despite 'knowing' that they are false. I continue to hold to them. But at least I stopped rationalizing them.

Part of the problem is that a person's beliefs effectively define them as a person. So to alter their beliefs can be very challenging; despite any weight of evidence. The best way to get someone to change their beliefs is either through reward or punishment. Unfortunately in disciplines such as philosophy there are very few real incentives or disincentives, so people are happy to continue with the status quo.

For the most part beliefs have more to do with psychology than reason. Even people trained in proper reasoning techniques are not immune to how powerful psychological affects are in terms of what we believe. Our psychology has a powerful effect on how we see the evidence. As most of you know, how we see the facts determine our conclusions. I'm not saying that we can't be objective. I'm saying disagreements are mostly over how we see the evidence or facts, and our psychology has a powerful influence on our ability to see the facts, or not see the facts.

Unfortunately in disciplines such as philosophy there are very few real incentives or disincentives, — A Seagull

Isn't it more that for those who cannot be persuaded by reasoned argument are likely to be less swayed by philosophy? So for them, a carrot-and-stick approach is more suitable.

The psychology of obstinance has been well researched. In addition to confirmation bias, there is:

1) Disconfirmation Bias: the tendency to set a higher standard for evidence that contradicts one's expectations.

2) Attitude Polarization: the intensification of disagreement as a result of confirmation bias.

3)Groupthink: closed-mindedness and poor social group problem-solving resulting from high group cohesion and insulation/isolation.

As far as persuasion is concerned, there are two ways to present a message:

1) Central Route: a direct (i.e., fact-based, explicit) presentation which is cognitively assessed (i.e., judgement based on argument strength) and intended to elicit agreement.

2) Peripheral Route: an indirect (i.e., emotion-based, implicit) presentation with cues processed by heuristics (i.e., cognitive short-cuts) and intended to elicit an automatic favourable response.

The peripheral route is much more effective than the central route, which is why there are better ways to persuade someone than by philosophical argument. I would suggest that persuasion is not the goal of philosophy, it is the goal of advertising, propaganda, etc.

The problem is that too many people have made an emotional investment in what they believe. They have connected their emotional state with their beliefs. It's not so much that they need to be right to be happy, it's that the belief itself makes them content, or that they are "disposed" towards a particular belief because other beliefs simply put them off and they can't mount a proper argument against it. It's just how they feel about it. Most people think if they just ignore the response, or the pointed question, then that makes it go away as if it never existed.

Everything is evidence of something. You just can't ignore certain facts. You have to account for them in some way and that way has to be consistent with your other beliefs. For instance, some ignore the existence of religion and some ignore the existence of consciousness. Whether it's just a delusion or an illusion, it still needs to be explained why it is so, and your explanation needs to fit with the rest of your puzzle pieces of your overall worldview. Too many people don't integrate their ideas into a consistent whole and end up being inconsistent.

The problem is that too many people have made an emotional investment in what they believe. — Harry Hindu

Or a cognitive investment. People will resist dislodgement (jenga-like) of a key proposition in a mental model, especially if the model has become complex over time through assimilation. Upon dislodgement, the model may require modification (due to partial collapse) or replacement (due to total collapse).

Too many people don't integrate their ideas into a consistent whole and end up being inconsistent. — Harry Hindu

Which results in cognitive dissonance.

For the most part beliefs have more to do with psychology than reason. Even people trained in proper reasoning techniques are not immune to how powerful psychological affects are in terms of what we believe. Our psychology has a powerful effect on how we see the evidence. As most of you know, how we see the facts determine our conclusions. I'm not saying that we can't be objective. I'm saying disagreements are mostly over how we see the evidence or facts, and our psychology has a powerful influence on our ability to see the facts, or not see the facts. — Sam26

While I am not disagreeing with you, I would add that the foundations of psychology are themselves logical and reasonable and so psychology cannot be entirely separated from reason.

..disagreements are mostly over how we see the evidence or facts — Sam26

If seeing something is the evidence, then the disagreements are not over how we see it but how we interpret it. The question "How we see it?" is already answered: "By seeing it", referring to how anything is seen.

That makes a lot of sense, in fact there have been some studies done on the neuroscience of belief change. They demonstrated that when people were challenged in their deeply held political beliefs, areas of the brain associated with self representation lighted up, suggesting some relationship between the two. You might like to look it up, the study is called "Why the Brain Wont Change Its Mind".

I'm not saying that we can't be objective. I'm saying disagreements are mostly over how we see the evidence or facts, and our psychology has a powerful influence on our ability to see the facts, or not see the facts. — Sam26

What kind of beliefs are we talking about here? Let's take the example of beliefs about the best way of governing a country. The psychological proclivities at play in the struggle between the Chartists and the political establishment in the 19th century reflected--more than that, were subsumed by--the social struggle between those who wanted to maintain exclusive power for the upper class, and those from the working class who demanded more power. What are the facts here that one or the other side could be right or wrong about? Both had their rational, but contradicting, arguments. The establishment could point out that the best governments of the past have been monarchies or aristocracies; and that even in Rome, where the plebs had their tribunes, social order depended on the power of the Patricians; and that ancient Greek democracy was unstable and led to mob rule, the execution of Socrates, etc. This is evidence, but the Chartists were not irrational to dismiss it.

The point I'm making is that a substantial proportion of beliefs are like this, that political and ethical beliefs are not necessarily secondary to, say, the belief that here is a hand or that human beings have caused changes to the climate. But are they different in kind, and how so?

This is actually quite topical, because the political and economic establishment of the UK argued against Brexit last year partly on the basis that it would cause economic problems, i.e., that there was a set of facts, presented by leading economists, that the Brexit supporters were irrationally dismissing. But what drives Brexit is in form similar to what drove the Chartists: it's what you do and how you do it that counts. Facts in this context are made, not merely revealed.

Hence, "The philosophers have only interpreted the world in various ways. The point, however, is to change it."

Most people, in my experience, don't even care about the facts, especially when it comes to religion or politics. They associate themselves with the group, or a group, and they follow that group - the facts be damned. And if they point to the facts, it's the facts the group associates themselves with - some may indeed be facts, but others are facts as seen by the group (real or not). All you have to do is look at politics, one side creates a narrative regardless of what the facts are, and those associated with that group simply accept that narrative true or not. Those that create the narrative, do so to stay in power. They do it because they know if they create a certain narrative, and keep repeating it, the group will simply follow. It's a kind of group psychology.

There are facts, that I wouldn't dispute, but most people don't take the time to sort through what are or are not the facts. They don't even have the time. They're too busy living their lives, so they just buy into what sounds right to them. What sounds right, is right. Those in the UK who were for Brexit probably didn't have a clue what the facts were, and the same is true for those who were against it. This seems true for most of those who believed one way or another. Are there facts that support a particular conclusion one way or another, yes, but most people don't have a clue what those facts are. This is where group think comes in, people just follow the group, like sheep. You see this in religion especially.

The problem is that too many people have made an emotional investment in what they believe. They have connected their emotional state with their beliefs. It's not so much that they need to be right to be happy, it's that the belief itself makes them content, or that they are "disposed" towards a particular belief because other beliefs simply put them off and they can't mount a proper argument against it. It's just how they feel about it. — Harry Hindu

That's because people commonly think what they believe true shouldn't be contradicted by fact. Philosophers should be able to consider their beliefs are wrong, regardless of facts demonstrating them true, and vice versa.

For the most part beliefs have more to do with psychology than reason. — Sam26

Belief (a propositional attitude) and reasoning (a cognitive process) are both psychological conditions. Belief (a proposition accepted as true):
1) Can be rational (based on reasoning), or irrational.
2) Is not fact (verified truth).

Belief (a propositional attitude) and reasoning (a cognitive process) are both psychological conditions. Belief (a proposition accepted as true):
1) Can be rational (based on reasoning), or irrational.
2) Is not fact (verified truth). — Galuchat

The act of reasoning, i.e., using logic to come to a conclusion is not a psychological condition. I would say that using a dictionary (if that's where you got this) is not the best way to come to a conclusion on this subject. It's no more a psychological condition than solving a math problem using the rules of mathematics. I agree that a belief, which can be propositional, is something we accept as true, and that these beliefs can be based on reasoning (correct or incorrect reasoning), and can be rational or irrational depending on how we reason, or depending on what led us to the conclusion.

Beliefs are states of mind, but it's the act of reasoning that I'm referring to when I talk about reason. How we use propositions to come to a conclusion. Most of what people believe, or a large part of what people believe has nothing to do with the act of reasoning - the act of drawing a conclusion.

The act of reasoning, i.e., using logic to come to a conclusion is not a psychological condition. I would say that using a dictionary (if that's where you got this) is not the best way to come to a conclusion on this subject. — Sam26

Where does reasoning happen? In your mind or somewhere else? What is psychology (I would recommend using a dictionary)?

You're not wrong, I never think that I am but I sometimes still doubt that I'm right. What I'm saying is that I'm not really avoiding confirmation bias but I'm looking instead for information to prove my viewpoint beyond doubt.

Have you ever wondered why it is sometimes so hard to get people to change their mind? Sometimes, it seems that no matter how much evidence you provide for someone against their views, they refuse to acknowledge it. Well, this is due to a cognitive bias that is hardwired into all of us, namely, Confirmation Bias. It is a tendency to filter out information that contradicts our assumptions, and exclusively pay attention to evidence in favor of them. It is truly amazing how this shortcoming in our reasoning affects us on all levels of communication, politics, social media, the news, and more. — rickyk95

A problem with this is that just because one person says "I believe A to be true" and another person says "I believe A to be true" doesn't mean that the two experiences are identical.

I could say that I like the taste of vanilla bean ice cream and you could say that you like the taste of vanilla bean ice cream, but the taste that I experience is not necessarily the same as the taste that you experience.

The whole idea of the existence of confirmation bias seems to assume that a belief experience by one person is a neurological and spiritual carbon copy of a belief experience in one or more other persons and that we can therefore observe confirmation bias by presenting evidence to all persons that contradicts some random person's (the researcher, maybe?) belief experience. But are they really the same? How do we know?

I don't think confirmation bias is an unequivocal philosophical sin. Look at the flip side - perpetual doubt leads to paralysis of thought and action.

Perhaps there's a good reason it evolved, if Darwin has any credibility. We can make decisions and act on our beliefs.

Everyone is different and learning in their own way in their own time. Discussions can be convincing or they can be about learning. It doesn't have to be about convincing.