I once thought belief was a matter of choice -- being of the mind, the mind decides what to believe or not.

Now I realize that can't be so.  There are two things seriously limiting our freedom to choose what to believe -- indoctrination and the reality checker we have that keeps us at least relatively sane.

If my boss tells me I am fired, I can't "choose" to believe otherwise.  Our brain's reality checker can identify such a thought and nip it off.  Problems happen when we already believe things (from education or from indoctrination -- it doesn't matter which).  The reality checker compares a new piece of information with what we "know," and either accepts it or rejects it.  If something doesn't fit in our existing beliefs, the reality checker rejects it -- and then often goes on to figure out rationalizations or excuses for why our existing beliefs should prevail.

To actually choose what to believe would require a level of mindfulness far beyond what any of us are likely to achieve, and would probably not be a good thing as our choices would then become either random or maybe personality driven, and this is tantamount to insanity.

The end conclusion I draw is that beliefs are a bad thing.  They are furniture we sit on without noticing their presence, but they control us a lot -- a hovering presence controlling us, especially when the beliefs came from indoctrination and therefore are either false or at least not properly supported with evidence.

The secret to breaking indoctrination is well known -- "cognitive dissonance."  Unfortunately some people are so rigid and arrogant about their beliefs that no amount of evidence raising doubts is allowed to penetrate.  Further, the memes (mainly religions but also other ideologies) that provide the indoctrination have built into themselves tricks for providing the indoctrinated person with rationalizations to get around even the strongest evidence.  The best example of these tricks is "faith" treated as a virtue and not as the serious vice it really is.

In the end if we want to be spiritually and intellectually mature and honest with ourselves, we need to abandon all beliefs and realize that nothing is certain, that the best we can hope for are reasonable, evidence based opinions.  Some things, of course, we can almost treat as beliefs -- such as the proverbial "the sun will come up tomorrow" -- but even here we cannot be certain, just asymptotically close.