Good and Evil are the forever topics in history, life, and well, humanity. While discussions usually tend to move towards moral doctrines and judgments, I came to see it more and more as something fundamentally related to the properties of life.
I suppose that I’m a rationalist and naturalist, so I tend to seek natural explanations to everything I observe or experience, which of course, includes the issues of Good and Evil. If one makes an effort to understand what living beings are, one may agree that many forces exist to destroy the delicate state we describe as living. At the molecular level, living beings have rather organized structures that are prone to the destructive effects of radiation, mutation, or simply the second law of thermodynamics (which states that all things tend to become more chaotic over time). On a higher level, organisms are under the constant threats of sickness, predator, resource depletion, and factors that could easily change the state of being alive. At the society level, wars, inadequate social structures, anti-social behaviors, and aggressive foreign societies could also destroy the fabrics of the society and threaten the livelihoods of the people within. In short, it’s not an easy task for living things to stay living. In many ways, the existence of living organisms is indeed a miracle in this universe we are in.
And if we look closer, the concept of Good is often times associated with the living, the reproductive, the creative; while Evil is associated with the dead, the sterile, the destructive. This brings out a point: for living things, Good means to stay alive, and Evil is whatever that threatens the state of being alive.
So naturally, as living beings, we try very hard to side with Good in the fight against Evil. We try to remain alive for as much as we can, for as long as we can, as all other living beings do. In fact, this struggle probably began in Day One when the first proto-life came to exist on this Earth.
So hence the eternal struggle that we shall carry on with us, as we try to fight against all things Evil in the name of Good, for reasons most of the time, most of us do not quite understand why (however, a positive regard to Good just feels natural).
But this “why” isn’t too difficult to understand, and it can be understood without moral or supernatural explanations. Good is simply the essence of being alive, while Evil is otherwise.