This photo meme is going around the interwebs lately. I love the message, it's beautiful and inspiring. But at the same time, it denies the very basics of human nature. We are not born blank slates. Human beings are largely shaped by evolutionary psychological adaptions that are encoded in our genes.
Our ancestors survived the very dangerous world of the past by forming groups, largely family groups. This grouping allowed them to protect themselves from other tribes who might try to steal their food or kill them. It helped them instantly identify a person of another tribe who might be a danger. Sure, we don't need to do that anymore, but we don't need an appendix anymore either and it's still in our bodies, just waiting to burst.
In this study a group of white children, whose parents never discussed race with their children (preferring to assume the "blank slate" theory will lead to children who don't even see race) watched some multicultural videos. Later the majority of these white kids answered "how many white people are mean?" with "almost none." And they answered "how many black people are mean?" with "some" or "a lot."
We have evolved to prefer being with people like us. This applies to everything - we prefer to hang out with people who share our interests, who have the same political and religious beliefs we do and, yes, people who look like us.
Prejudice is natural; but natural does not mean good. We do thousands of unnatural things every day, and they make our lives so much better. Parents, family, society has a responsibility to the children to teach them that is is OK to notice differences in other people, but teach them that the differences are what makes us interesting.
Overcoming prejudice is the mark of an evolved, sophisticated person. Perpetuating prejudice is ancient tribalism and the sign of a scared person.
For more information about the reasons the "blank state" theory don't hold up, check out this book:
The Blank Slate: The Modern Denial of Human Nature by Steven Pinker