Humans can be good but along with goodness comes evil. Good and evil can be described in many ways. Many people judge by the way they look. For example if you see a little girl with a yellow dress on you might say shes sweet and kind but you never no because your judging by looks. In the story "The Most Dangerous Game" by Richard Connell, a character named General Zaroff played out to be evil but at first the author made him seem nice by the wayhe let Rainsford in his home. As its quoted "... great pleasure and honor to welcome Mr. Sanger Rainsford... I've read your book about hunting snow leopards in Tibet, you see,...". The reader must have thought he was sweet for letting him in but as soon as the reader finds out what he does he won't seem so sweet anymore. Along with evil comes good. In the story "The Sniper", the sniper is sent to kill an enemy but does he know who hes going to kill? As soon as the sniper does kill the enemy and finds out who he is its a little to late to take the bullet back. As its quoted "Then the sniper turned over the dead body and looked into his brother's face ." The good about this is that he killed his enemy but the bad is that he lost a family member. See good and evil can't be against each other cause rather you like it or not good and evil will always be around you.
References: "The Most Dangerous Game" By Richard Connell "The Sniper" By Liam O'Flaherty