Research is going on in bridging disciplines of social science and psychology to investigate how much of our attitudes are learned and how much are inborn (genetic).
A recent study in the Scientific American Mind explains that the majority of humans beings initially have a subconscious stereotype for differences other than their own, remnant of the 10,000 year ago tribal life where it did enhance survival. Civilization and liberal democratic ideals are a cultural, learned phenomenon of very recent origin, the result of telling a new story about how we should live. 10,000 years ago which is the most recent major phase of human evolution according to the best of current science, members outside of one’s own tribe were likely to kill or capture members of another tribe as the concepts of selflessness had not been thought up yet. This does NOT mean we were not then interconnected; we were, but we were not aware of the kind of ethical notion of selflessness and altruism we have developed today in a civilized society.
So, the inborn tendency to fear others that are different is a problem that is far deeper than one person’s ignorance or overactive ego, and our job is to play the all important role of promoter of useful and positive ideas that will ultimately become the new inborn tendency.
Here is the interesting part: as soon as a person of a particular group learns to pay attention to differences of individual members of other groups than his own, he becomes less and less fearful and therefore more tolerant of others. We have all heard the saying at one time or another perhaps that “individuals of a particular ethnic group all look alike”. There is a genetic basis for this, and all genetics are causally arisen from some previous attitude or behavior and did function to enhance the ability to live on earth successfully.