Having beliefs is a difficult matter. They tend to be complex and embedded mental states difficult to identify. Changing them is even worse. Beliefs have their own mental gravity. They tend to stick on their places as they are supported by more and more beliefs as time goes by.
I think there are two reasons for this latter difficulty. First, following Pierce, acquiring beliefs is a matter of tranquility. Easiness, calm and satisfaction come with them. Recent studies with amnesiac patients have been able to prove this general claim. The level of stress associated with the feeling of knowledge is higher in these cases. It is, literally, psychologically disrupting and, hence, physiologically expensive not to have a belief about something and, thus, not to have the feeling of knowledge for that matter.
This expensive emotional mechanism attached to our epistemology seems to prove useful when it comes to find out what the environment looks like. It is expensive, though, when we must change this view. And this also seems to have a reason: it is really expensive, dissatisfying and unbearable to stay in doubt than to believe. So we will inevitably end up with a story. Think, for example, on how even in Matrix-like situations, we end up building a story. The Matrix, at least, is to be charged with the explanatory burden. Thus, it is chemically, mentally and, also, time consuming to change our beliefs.
But that’s not the whole story. There’s a second important problem to be mentioned: this is the fact that most of the time we don’t know how to modify our beliefs. Belief revision and, furthermore, belief substitution, is a highly complex metacognitive task. Think of each one of your beliefs as a thread of whole that forms part of a bigger fabric. If you find out that you cannot keep that line, or anything like it, and neither can you replace it with anything similar to it, like another piece of whole, how would you patch the fabric? Or put it this way. Say you’re told you have to take off a squared-shape piece of your house, and that you can’t replace it for just another square-shaped block of the same material. How would you do this?
This is how belief substitution looks like. Beliefs are always embedded within more beliefs. Hence, changing one most certainly requires changing more; and so, a more general architectural work is needed. Furthermore, beliefs are defined also by the way they are embedded. Thus, finding another belief with exactly the same inferential pattern won’t solve the architectural problem. This makes the task of changing our minds an incredibly difficult one. And things can get worse the deeper and stronger the beliefs are.
Thus, not only is it physiologically painful, mentally uneasy, and time consuming to change our minds. To change our beliefs also requires a degree of wisdom and self-knowledge. One must be able to identify the belief and, thus, the way it is embedded within other beliefs that support it and/or are supported by it. Furthermore, one must be able to come up with a new story, a different account of things, in order to replace it.
Asides from the fleeting beliefs about the immediate surroundings, those that we automatically substitute while keeping track of space and time (e.g. I started believing it was 5:25 am, I now believe it is 5:59), it is very difficult to revise our beliefs. We are never told how to do this. No one ever claims that this is what learning is supposed to be about, and so we rarely, or very painfully, learn.
It hurts so much to change our minds. We need to build up new and different ones.