In physical appearance, they differ due to differences in genetics and the language can be widely dissimilar, but inside they have the same chemical reactions. One example is a baby with Down's Syndrome. In pictures, they often look like twins. This reinforces our belief that notwithstanding the difference in other appearances, a product of geographical environment, people inside are the same. Everyone knows the stereotypes associated with people of different races.
People are often distrustful of people from other races and cultures.
However, when we see a person in terms of his inner traits of compassion, honesty and sincerity, we should be reassured. Everybody is aware of the predictable reaction one will have if a girl marries a boy from another race. Then we discover that this man is moved by the same spirit of honesty, sincerity, or compassion, which we idealize in our own society, we are no less shocked. The moral courage of a girl to jump her social barriers makes me wonder that she did not come from an orthodox Hindu family. Inter religion marriages are still looked upon with suspicion and disapproval.