Let's look at two extremes. Mind A is a completely open mind; it weighs all input as equal no matter what logic, experience, or anything else says, leading to extreme cognitive dissonance. Mind B is a completely closed mind; unless new input conforms to what the mind already knows, it will ignore it, leading to no cognitive dissonance.
I have never heard of anyone at either extreme, but I have met people very close. Let's create a range of -1 to 1, where a score of -1 relates to a completely closed mind and a score of 1 relates to a completely open mind. We'll call this the mind's openness score. Those in the lower 15% or so we'll call dogmatics; they are set in their ways and nothing will ever change them. Those in the higher 15% or so we'll call sheeple; they will change their mind every time someone gives them new information.
Question 1: Is the openness score fixed for a given mind?
Question 2: If the score is fixed, which value is optimal for a mind? What is the balance needed to allow a mind to stick to their values, beliefs, and goals but open enough to change them given the right input?
Question 3: If the score is dynamic, what causes a change? Is it age? Is it the input itself? What type of input causes larger or smaller changes?
This strikes me a bit like a bias in an artificial neural network.