Darkness does not exist. It's the condition of the absence of light.Hmmm... what do you think, does darkness exist? Darkness is the condition without light. Similarly, evil is the condition without good. I think it is possible that people are without good and when they are not good, don't do good, it is called evil.
And addressing what's in bold, you're saying that if we don't do good, then it's evil. If that's true, then answer this question. Are you committing an evil act if you're standing still?