Is it possible to experience an evil that teaches us nothing?

Welcome reader.
There is an expression in Spanish that says "no hay mal que por bien no venga." It translates roughly to "there is no evil that comes without good." The idea is that even when things happen that may appear bad or evil to us, there is a lesson to be learned or unforeseen consequences that reveal a kind of silver lining.

This expression made me think about what I believe about the nature of good and evil and more importantly how they relate to each other. I profess I am coming from the Christian tradition when I think about this particular issue. With that in mind, as a saying it appears to hold true. Even the most tragic and horrible events that have affected mankind did in fact have consequences and effects that could be seen as benefits. This is not to say that these benefits were on par or outweighed the harm, only that there is indeed a silver lining. To take a mundane example, let's say that you are in a monogamous relationship and your partner cheats on you. Most people would describe that as an evil act that ought not to happen, but even this act of singular selfishness can have a silver lining. It gives you new insight into who that person is and into the health of your relationship, insight that would have been difficult otherwise. That insight is new knowledge that can help you make informed decisions in the future, and thus benefit, in this case by leaving your partner and finding someone who can respect you.

I am sure that you, dear reader, can come up with dozens if not hundreds of similar examples. I am hunting a more elusive scenario, where a tragedy happens with no lesson, no good consequence, no silver lining. This thought experiment might be controversial, trying to imagine a possible good from the worst tragedies mankind has seen. To pick an extreme example, even the Rwanda genocide, which is safe to say was a great evil to befall that country, has some good come of it, even if the form of forgiveness and understanding on the part of some of the victims in the years after. There are many heart-warming stories of human kindness that come out of even this tragedy, not to mention stories of compassion and bravery during it.

The only thing I could think of as being thoroughly evil, without any seed of goodness, had to be the hidden act. Evil that is hidden denies everyone else the opportunity to learn, grow, and move on. Something like treachery that goes undiscovered, born of a selfish and self-serving will, must be the kind of evil that befalls a victim without any silver lining.

This may not seem satisfactory to you, reader, because you may pause to note that in this example the victim may not realize that an evil has been inflicted. And you would be correct. Humanity has an amazing capacity to see evil and selfishness everywhere, and an equally powerful capacity to see goodness when they care to look. But denying a victim even knowledge of a sin inflicted upon them gives them no chance to learn from it, to work through it, to truly move on.

There are those who believe that good cannot exist without evil and that evil cannot exist without good. I think that for the most part this is true. Apart from the consequences of actions, which is what I have been focusing on in this post, there is also great complexity within people themselves, even those who could be appropriately described as evil. That however is a discussion for a different day.

Please let me know what you think in the comments below. Do you think there can be an evil that is only harmful? A tragedy with no silver lining? Why or why not?