Much is made about people being products of their culture. But this fails to explain radicals within a culture. Why did some people growing up in Nazi Germany hate the Nazis? Why do people try to run away from N. Korea? It's quite clear that not everyone conforms, not everyone bows down to cultural pressures.
I think this is because some people are more objective than others. Some people have a natural tendency to evaluate everything according to what helps their physical health and constitution, knowledge, skills, and ability to learn, and managing their environment. If through social interaction and logical reflection they come to see other people as part of their environment and hence as important and reflect on what's best for those others they will construct what they see as good for those others and for society on such an analysis, and at best their ideas can produce things like the Enlightenment, and promote the expansion of civil rights. At worst these people grow up to be criminals or turn their objectivity towards exploitation to further selfish interests. So these outliers can do great good or great bad, but we need them to prevent degeneration of our society into a giant cesspool of groupthink. We need people who can sound the alarm when the group is about to jump off a cliff.
This "outside looking in" perspective on society must exist to varying degrees among people and have some influence because everything has to come from somewhere, otherwise all cultures would have random values. While this more objective way of looking at things is clearly distorted for most people it had to distort from somewhere in the first place.
Suggesting this is natural is not to suggest this is purely based on nature. If you make an effort for it you can improve your objectivity. As well this is just a disposition, since no one has knowledge of everything no one can be completely objective but a person can tend to prefer making decisions towards more objective goals such as physical health and constitution, knowledge and skill acquisition, and managing their environment.