As decades roll on, we tend to become tired of all types of conflict, outer and inner. Black & white thinking, being the rabid fan of one cause while vilifying its apparent opposite(s) becomes obviously inappropriate. Harmonizing, or perhaps more accurately, recognizing inherent harmony as we open to the bigger picture, feels far healthier.
One of the overarching paradoxes to outgrow is black & white thinking itself - if I hold one particular idea, then all other ideas about the same topic are wrong. Depending on the specific idea, rigidity about it can easily escalate to cause great harm to self and many, many others eg religious exclusivism: one religion is true, all others are in error. How this "error" has been & continues to be "corrected" appears, paradoxically, more diabolical than holy. The Dalai Lama and the present Pope are trying to bring a mature, intelligent perspective to this paradox.
Another overarching paradox is how each of us is both a hurt, needy inner child, and at the same time, a wise grandparent. As we mature, the former "acts out" less & less. When we do behave inappropriately, we accept and unconditionally love ourself, make amends for the harm we may have caused, and seriously resolve to behave more wisely in the future. To the extent that each of us fails to recognize, accept & heal our hurt, needy inner child, we externalize, projecting our unresolved psychological baggage ("sins") onto others, and cause great harm & suffering.
Perhaps the most subtle & useful of life's many paradoxes to harmonize is this:
"Everything is perfect, but there is always room for improvement." Shunryu Suzuki