4 Factors which impede change of beliefs
The first is confirmation bias. Confirmation bias (Nickerson, 1998) happens unconsciously and has three aspects. The first aspect is that we are inclined to look for information which confirms our previous beliefs and hardly to search for information which may contradict them. The second aspect is that we perceive and interpret information in a distorted way. We are inclined to see in information we are confronted with, a confirmation of our beliefs. The third aspect is that we can remember information which confirms our beliefs more easily than information which disproves them.
A second reason why it is often hard to change our deeply held beliefs is that these beliefs restrict the range of our future experiences. If we, for example, believe that a certain type of people can't be trusted, we may approach them, perhaps without even being aware of it, reluctantly or even hostile. This behavior of us may evoke a defensive or hostile reaction in them. Subsequently, we may indignantly conclude that we were right: "They're no good!" Without us realizing it, our belief has become a self-fulfilling prophecy.
A third factor which may impede the changing of our beliefs has to do with the fact that we sometimes strongly identify with our beliefs. If we label ourselves according to our beliefs ("I'm a conservative, always have been, always will be!") it becomes harder to change our beliefs. Holding on to your beliefs more or less becomes a matter of honor when your beliefs coincide with the core of who you think you are. If your beliefs turn out to be wrong, can you yourself still be right?
An extension of this problem is the fourth obstacle to changing your beliefs: social pressure. When groups declare that a certain belief is inseparably connected to the group, a big obstacle is created to change or let go of that belief. If you reject that belief, you run the risk of no longer being viewed or accepted as a member of that group. In this way, groups can hold individuals imprisoned in their ways of thinking, even when they are outdated.