Sorry, but this assumes the unbiblical view that Man is inherently good. We're not.
Behold, I was brought forth in guilt,
And in sin my mother conceived me. (Psalm 51:5)
See Romans 7. The biblical understanding of "Sin" (with an upper-case "S") is that it is more than what we do, more than transgression against a commandment; it is a deep "bent"-ness, a controlling power within us that makes us self-centered and rebellious against God. This has been recognized by Christians for at least 1800 years, from Augustine of Hippo's "Original Sin" through John Calvin's "Total Depravity". You DO see it in babies who want what they want RIGHT NOW, and to hell with everyone else's needs. And they'll scream until they get it. Sin is as natural in us as breathing.
7 What shall we say then? Is the Law sin? Far from it! On the contrary, I would not have come to know sin except through the Law; for I would not have known about Lust if the Law had not said, “You shall not desire.” (Romans 7:7)
Remember Luther and Calvin's "First Use of The Law": To identify Sin for what it really is. If you're going to go down that Romans road, make sure you remember your own sinfulness, and tell them the good news: That God loves them and Christ died for them.