Sin lies only in hurting other people unnecessarily. All other sins are invented nonsense.
I assume that you are not a Christian. If you are a Christian, your principle is nonsense. The first four commandments of the Ten Commandments have little or nothing to do with our relationships with others.
No that's a negative view of life. Incidently, "Do no harm" is the Satanic and Wiccan code. God requires much more than that.
God requires that we love Him with all our heart and love our neighbor as ourselves. That's an active love, not just an avoidance of harm.
A person who goes around just trying to avoid harming others, but never loving others is an evil man. God calls us to be much more than that.
In fact, God calls us to be perfect and Holy. "Be perfect for I am perfect". "Be Holy for I am Holy."
God is a perfect Holy God. He doesn't judge us on whether or not we've avoided harming anyone. He doesn't judge us on a bell curve of humanity where if you're closer to Mother Teresa than to Adolf Hitler, you're okay. He doesn't judge us like the Muslims believe on the scales of justice where if your actions are 51% good, you're okay. He judges us by His perfect standard.
That's why we need a savior. Because none of us can stand before a perfect Holy God in our own right and survive. We need forgiveness. And when our sins are washed away, then we are made perfect.
"Come let us reason together, though your sins are like scarlett, they shall be white as snow." "Blessed is the man to whom the Lord will not impute sin." "Whosever believes in me shall not perish, but shall have everlasting life." "But this man (Jesus), after he had offered one sacrifice for sins for ever, sat down on the right hand of God;" "By the which will we are sanctified through the offering of the body of Jesus Christ once [for all]."