I'm not sure "who" you are referring to, in your statement. But, this statement will always stand true......Intelligence is invisible to the people that have none.
That being said, you are forgiven because.....all humans have a inherent propensity towards ignorance.
Moreover, you see what you want to see. Your judgments and opinions are subjective in nature and are normally a construct of another trying to influence you by in a conformist manner; your ego blinds you from the truth. There is only good and lack of good.
Intelligence is inborn and there isn't much you can do about it; ignorance is a lack of knowledge and can be corrected. Don't agree there is only good and lack of good as in heat. I see plenty of outright evil out there and voluntary blindness to the truth is epidemic.