I think you're both right, to a degree. I think a lot depends upon who is doing the looking, and why.
With what CB said, this is true to the extent that a reader or audience is able to understand the enormous and unbridgeable gulf between the monster or alien or god and man. I see this analogously all the time while working cases.
The family of the victims, or someone else on the periphery of the case, or a rookie with no real experience of how these things work, will comment, "How could anybody kidnap and rape and torture and then strangle such a sweet and harmless little six year old girl, cut her body into pieces and then bury the remains twenty feet from his doorstep." People not familiar with this kind of thing and this kind of person (is that the wrong word? - well, yes it is, but it's what I got to use) think that if they just understood the thought and behavioral processes of the perp that they would magically establish a "link of understanding" between themselves and such a guy. That if they understood they could comprehend, and if they could comprehend it would all suddenly make sense.) But they never really will because the nature of such a subject, and the nature of those who fall prey to such people, are rarely the same type of natures. They both wear the suit of flesh that makes them appear to be men, but they behave in ways totally alien to one another, and have thought processes totally different. (I'm not talking about victim dis-similarities, but psychological dis-similarities.)
It's like Grendel in Beowulf. Sometimes Grendel is just Grendel. He doesn't behave as he does because that's what he has in common with the Geats, or doesn't have in common with men in general, but because that's the way he is. Grendel is Grendel, and maybe even he could change in the right set of circumstances, but he doesn't wanna change. That's what most people don't get. And don't wanna get. Grendel is the way he wants to be.
The Hussein brothers didn't rape teenage girls, tape their activates, and then feed the girls they had just raped to hungry war-dogs because of their high status in society, because of their educational background, or even because they were bored with nothing to do on a Saturday night. They did it because they could, that was their nature, and that's where they came from. There's nothing really to understand about it, other than the fact of how they operated. Not why they operated, but how. The why was entirely in them. And that's why they were the way they were, and why they wanted to be the way they were. Sometimes Grendel is just Grendel. You don't study Grendel to understand why Grendel is Grendel, you study him to understand how Grendel is Grendel. With the how of the matter it becomes easier to kill him, the why is never gonna lead anywhere but back to a lair peppered with bone-shards and pillowed with gore-pools.
But the point Mall was making (I think, but he was probably driving at it in a very different way than I'm going about it) is that the reader or audience, and especially the modern person, desires to understand, and honestly believes everything is understandable, because it comforts them to think this. Modern people actually think everything is resolvable, if you just understand enough about the subject, and that an acceptable resolution is always forthcoming from such understanding. That understanding someone naturally equates with resolution, acceptance, or similarity. The emphasis being of course that one stresses the idea that understanding will and can always occur. That it is a natural and inevitable result of the contact between what is alien, monstrous, and unknown. Therefore you stress what lies in common between audience and subject, even if it is small and subtle, not what is different, even if it is obvious and enormous. You don't wander too far away from the familiar, because the audience has either no desire to be reminded of the utterly alien, or just as importantly, doesn't really believe it is possible. And you can't convince anyone of anything they refuse to believe in, or assume to be impossible, a priori.
Personally I think the idea that man can reduce everything and everyone and every creature to human, or even decent or civilized understanding a ridiculous canard, and laughably naive. Juvenile in concept, and dangerously so. Nevertheless it is the rather ingrained and hard habit of the modern observer and of the educated modern man and woman, and even child, I would say. That it is so common and ubiquitous in our culture (including the assumption that Reason is a Universal God - but such assumptions are not standing positions in cultures like Somalia or Rwanda, where the idea that it is possible to understand everything, or even that one would want to do so, or that practice of this method leads to mutually beneficial conflict resolutions are viewed as alien - and I've personally seen everything but reason wielding machetes and butcher knives on unarmed dismembered civilians) that the idea is just accepted at face value as being unquestionably true regardless of circumstance, culture, time, or place.
It is sort of a sub-conscious facade, a mask derived from the constructs and beliefs of our own culture, which many of us place over our minds and through the lens of which we do color our assumptions about the world. But it is no more true, nor false, that those cultural and societal and psychological masks assumed by the Athenians during the Peloponnesian Wars. It is the way we see things, and the way most of us want to see things, regardless of the evidence.
Now that being said (and I think this is very much why our myths are all of Super-heroes like Superman and Spiderman and Batman, extremely naive and yet fundamanentally good and noble and well-meaning heroes, rather than of an Achilles or a Beowulf) a modern Author must play to his audience. Rarely would an Oedipus be accepted and understood and sympathized with in the way he was among the Greeks, nor a Cyrano among the French. You target the audience you possess, and you play to their values, and mores, and assumptions, and conceits, and psyches, not to the psyche of those who feel it is not necessary to understand the other, or who do not assume it is even possible or required.
So to me both points of view are right, it just depends at what point along the spectrum you are making your observations, and who is doing the looking, and what exactly he's looking at and why.