Do you think people are naturally moral or immoral?

Do you think people act in their own self-interest or act for the benefit of other people? Interesting question I got from my philosophy class. There's a story about a man with the ability to turn invisible, and he uses it for greed and power. The lesson is people would do bad things if they're certain they won't be caught. Do you agree?
Do you think people are naturally moral or immoral?
Post Opinion