It is difficult to find an adequate definition for the phrase "human being." Nothing I found comes close, taking into account the complexities of our species.
People don't live on the margins, none of us are all good or all bad. Our lives take place on a broad page with many choices. Good, bad, decisions we make that we would like to take back. We are all capable of great kindnesses and cruelties. Few of us would turn down the opportunity to hit the "do over" button of life and get a chance to change one aspect or another of our lives.