This vocation is constantly negated, yet it is affirmed by that very negation.
Dehumanization presupppose the human or the humanity, acknowledges that humanization exists.
In other words, for something to thwart another thing's existence that other thing must exist in the world. So by constantly thwarting the humanization of people, humanization is something that can be achieved. (This wording is confusing, but I'm sure I'll understand. I'm sure.)
