[Stepping away from the cultural commentary and scientific or political headlines. This is a philosophy lesson, drawn heavily from 4th century metaphysics. I hope you enjoy this blast from the past, repackaged and reapplied for today]

Evil seems to be real, yet in what sense can we say it “exists”?

Some, of course, say evil has neither existence nor reality. That position is logically possible, and some (otherwise) smart people have advocated it before. But it’s counterintuitive, morally bankrupt, and repugnant to our moral senses when faced with its full implications. One has every freedom to deny the existence or reality of evil. And, by implication, he or she is thereby refusing the privilege [responsibility?] of naming as”evil” the Holocaust, female-genital mutilation, or chatel slavery. But such brave souls should know that they are likely stifling in themselves the very epistemic senses that lead everyone around them to shutter at such hubris. Suppressing knowledge, even if its the amorphous categories of moral knowledge, is hardly laudible and likely misleading. And even though its possible for most people in the world to unite in error, if they unite in disagreeing with you, you might want to check your figures again lest their many minds caught a detail your single mind didn’t.

It is fairly safe then, at least by the limited evidence found in the general consensus of most of the world’s population, that evil is in some sense an existing reality. We are left then to explain how such apparent existence occurs.

One of the classic, and I think, strongest answers to this question is the “privation definition.”

The essence of the privation definition is that every evil exists parasitically, corrupting its host. The host can be thought of as some kind of goodness. That goodness can occur with agents–such as human beings, in which case it is moral goodness and evil would be some kind of compromise or corruption of that moral goodness. Agents can be “good” insofar as that are and do whatever they are SUPPOSED to be or do. If people are supposed to exercise justice, the good moral agent exercises justice.

Or the host goodness can occur as a non-agent like a weather pattern, a tree, or a tiger. Goodness, in that case, is a kind of “ontological goodness” not unlike that described in Genesis 1-2 where God looks on his creation and calls it “good”–even before he made human agents and before any angels or demons are named among creation. This “ontological goodness” refers to the positive existence of things (ie: they add something to the universe). Insofar as they are and add what they should, they are “good.” In the case of ontological goodness, evil would happen when an otherwise “good” natural phenomenon goes wrong, such as a deadly tornado, a tree-fungus, or a tiger attack.

That groundwork having been laid, we can get to the heart of my concern here. Evil is parasitic precisely because goodness is independent.

Put another way, there seem to be independent goods but no independent evils. That is, there are good things that have no need of a more basic evil thing among its causes. A loving man and loving wife can, theoretically, be perfectly committed to each other in love and responsibility and give birth to a cherished little baby. There is no need for “evil” to enter the scenario. But, every evil has some more basic good that it requires in its causal set, such as a good material cause or a good efficient cause. If that baby is born blind, that would be a natural evil–which could not exist if there were no good baby to corrupt (a material cause). You might call this unequal relation a conditional relation (symbolized in logic with the horseshoe). In contrast, we may look at the Taoist or yin-yang view of morality. By the Taoist view, evil and good are more comparable to a biconditional relation, wherein the two parties relate equally and exactly too to each other. For a Yin-yang view to work, good must be just as dependent on evil as evil is to good. But from the baby example, and the examples below we see that it clearly is not.

If a man murders an innocent person, it would have to be voluntary to qualify–legally–as murder. But volition is a good thing (ie: we can roughly translate it as “freedom”). But volition does NOT require murder. Hence, the evil of murder requires a good efficient cause in the form of volition though volition does not require any such evil.

If there were no sexuality (good) there would be no rape (bad), whereas, there is no need for rape to have sexuality. Hence rape requires a good formal cause (ie: healthy sexuality) which does not itself require the evil of rape.

There is no arrogance (bad) without valuing one’s self (good), but valuing one’s self does not require arrogance. Arrogance thus requires a good abstract material cause of valuing one’s self which does not, in turn, require manifestation as arrogance.

There is no football injury (a bad thing) without the sport of football (a good thing), but the sport of football does not require an injury. Hence, football injuries require a good concrete material cause in the sport of footbal though football does not itself require any injuries.

Pretty much every evil I think of operates like this. So the philosophical “privation” definition of evil is fairly defensible when we consider good and evil, not simply as contrasts, but rather with consideration for their causal dependence.

Evil thus proves to be a parasite. Both evil and goodness exist and are real, but evil is always dependent whereas goodness can be independent.