One of the most important aspects to the nature of evil, or of interpreting life generally, is understanding perspective versus reality. The nature of truth, especially in the realm of relativism, is based on perspective which ultimately occurs in experience (or what one deems as reality). People who anchor in relativism will ultimately rest in the principle of the ends justify the means (as everyone seeks to assert their ideal or version of good and evil); while people who anchor in biblical truth assert that loving God and other people is the only way to create a sustainable world. Unfortunately, these two approaches to sense-making and a sustained way of life are not compatible. Even in the Epcot or League of Nations ideal, each nation or tribe will be sustained or governed by self interest, which inherently lend to pushing for greater power or control and conflicts with other nations where mutual self interest is not available. Why else would our history be bridled with wars and a musical chairs of empiric rulers?
Evil by nature exists through the conflict of personal desire versus universal interests. Evil actions occur when the interests of one person or party come at the expense or detriment of another person or party. Let’s use murder as an example. The person that takes another persons life often has a motive (money, anger, etc.) where they unilaterally determine that ending another persons life is in their own best interest. It encompasses all scenarios including self defense where you determine your life carries more value than the one who seeks to take your own. While many would agree that murder is evil (which can only be true if you have an ontological source, otherwise murder in a video game could also be deemed as evil as murder in our physical reality), it still happens all the time. Why does this happen? Because actors in the current system believe their own interests exceed that of others, it is the selfish intention that causes all sin, destruction, and pain. Hence the nature of capitalism is cannibalistic to the extent where mutual growth is not an option; it happens all the time and why laws are needed to limit even more evils from occurring. On the converse side, we see the ills of socialism, as people are just as happy doing nothing than contributing to society (pure self) with Universal Basic Income.
As a result, in a world of relativism, one needs to understand perspectives and intentionality. Let’s take the hypothetical scenario of would you go back in history and kill Adolf Hitler if you could? I’d imagine a great deal of people would say yes, justifying that the one evil action could limit all of Hitler’s evil actions. However, that might not be the case. Hitler led a depressed German people that were oppressed by the US and Europeans following World War 1. Chances are some other revolutionary leader would have risen up due to the oppression of the developed western nations, and that even removing that oppression would not have changed the imposition of various nations and their own self interest. The only difference is that you would have become a murderer and face the fracture in your soul balance. That might lead to even more destructive actions as since you have now killed someone, and what else might you do to justify your ideal scenario? See the paradox and how it pushes into an end justifies the means mentality backed by the source conflict of personal self interest versus universal compatibility?
Perspective, intentions, and universality are the source keys to understanding why evil exists and exists outside of God. God has the capacity to do unbridled evil, but from perspective and intention, he chooses not to as His goal is a loving relationship between him, his creation, and between them; the only scenario that supports a universal, eternal and heavenly existence. Yet, realistically, that version of heaven would be like hell for others. There would be no status or hierarchy, there would be no need for ownership or laws (no marriage union would be necessary, love wouldn’t need a contract), there would be no reason to pursue excess as everything would be readily available for all. For many, the idea of not attaining more than someone else, a constant pursuit of flesh based desires (seven deadly sins), or not pursuing self interests to its greatest form is worse than the universal loving state provided by heaven. That’s why perspective and intentions are important to understand, as the principle of universality or sustainability only work if everyone in a society share the same objectives and the society is capable of growing perpetually. Hate to be the bearer of bad news, no society of haves and have nots, power and no power, or without mutual love and respect among all people will ever sustain.
To give another example of perspective, let’s address Lucifer. From his perspective, he thought he deserved a nicer Kingdom than he had, hell, he thought he deserved one nicer than God. He was attractive and wise and no one was as great as he was. He should be worshipped, as are all who are like him. To not understand that is oppressive, a denial of beauty and power, and the basis of ignorance. This basis formed the conflated egotism that we have today. Most people, most nations, governments and companies are guilty of this form of pride or self seeking ambition. Look at our leaders, our celebrities, and what people truly value. Look at the culture and value systems you were brought up in. What do you value and how do you support it? Would society be better or more functional if everyone was like you or did what you did? The exercise in honesty will help you realize what works. A society of homosexuals would die in a generation, a society of anarchists would constantly be at war, a society of artists would die of starvation, the list goes on… but there are many who prefer and empathize more with unbridled self will than loving harmony.
In conclusion, evil exists merely as a function when self will exceeds universal compatibility and is the reason for so many issues. God did not author our pain, but he did know how things would play out had we taken of the Tree of Knowledge. He started us out in the ideal, and will bring those of us back who follow Christ in the path of mastering duality and choosing good only, which is really what happens when you accept grace or make it to heaven in the Great White throne. It really is that simple, but many get confused when they allow assumptions to block them from getting back to the simple dichotomy that can really only be traced back from the creation narrative itself.