This is a hard question to answer if you are not allowing genetics or environment into the equation. Even so, I would say that most, not all people are inherently good. I can not say all, because I believe that some people are, in essence, born evil. Why inherently good? Take two children and raise them in separate families. Place child one in a nurturing, supportive environment; child two in a hostile, neglectful one. I do not have the statistics to support this, but I believe due to the inherent good in all of us it is more likely for child two to be a positive influence on society than child one being a negative one.
Also, because most people don't go out doing harmful things to each other regularly and deliberately, this also shows humanity's inherent good.
Or I could be devil's advocate and give an equally weak argument for society's inherent evilness. . .