What are the philosophical underpinnings of growth versus fixed mindsets?

As a former Southern Baptist minister I have seen the effects that the "Original sin" mindset (as well as other Biblical doctrine) has on believers. This doesn't seem to have as much of an effect on younger people so much as it does older ones such as my parent's generation. To tell someone "You are flawed by nature" then turn around and say "God doesn't create junk" or "God never makes mistakes" is confusing and contradictory. Yet believers of all ages cling to these contradictory "truths" as absolute fact.
I have seen first hand the narrow mindset and unwillingness to question ones faith and the world that it fosters. In my opinion any faith that is not examined (blind faith) is dangerous. This type of blind faith is what breeds terrorists and extremists.
To be honest I have sat here racking my brain about this and I the only fixed mindset thing I can think of at the moment is racism. I think this is possibly the worst plague our society faces. It stifles mental as well as economic growth and promotes hate on both sides even where it didn't exist before.
Yet, maybe racism isn't the real problem after all. It may simply boil down to hatred.
Hatred can extend to many things besides race. Hatred is well established in our political system and is used far too often as a tactic to garner votes. Hatred of change can keep a person, business, town, city, or state from making changes necessary to help it grow and prosper. Hatred of a person can cause someone to see only the negative aspects of the target of their hate no matter how good they might actually be.
When hatred holds sway on someone's mind it prevents reason and logical thinking from being employed, therefore growth is negated.