We understand the meanings of certain terms by implicitly appealing to their antonyms. We invariably approach semantic meaning in this way when interpreting the meaning of terms involved in conceptual dichotomies. For instance, when someone says "Oh, it's already light outside!" we interpret the meaning of "light" in contradistinction to the meaning of "dark." The concepts of light and dark together constitute a binary. Skepticism toward binaries has become popular today. In my field (sociology), to prop up a binary is essentially to commit a sort of sin. Binaries are considered oppressive, exclusive, over-simplistic. This skepticism can be important and necessary, but blowing up conceptual binaries is not as straightforward as it may seem.
Take light and dark. You can re-conceptualize the light/dark dichotomy in terms of its constituent categories. This process requires translating one of the categories into a unit such that instances of the discarded category are reconfigured as unit quantities of the retained category. In other words, the degree to which a thing is dark can be expressed as the quantity of light units it possesses (or vice versa with dark units). Instead of describing the night sky as "very dark," we could describe it as "possessing very little light." Notice that if we accept a re-conceptualization of the light/dark dichotomy as a spectrum of units derived from one of the binary's original categories, we forfeit the ability to ask certain kinds of questions. For instance, if we re-conceptualize the light/dark binary as a light-unit spectrum, we can no longer ask "Is that thing dark?" Darkness is no longer a quality things can possess under this new rubric. Since there is no longer a dichotomy of light versus dark (or not-light) and only quantities of light, we can only ask "How light is that thing?" So while a re-conceptualization of this sort may make philosophical sense, problems arise when attempting to employ it practically in conversation.
Before delving into two negative consequences which can result from blowing up binaries in this way, it is worth noting how frequently people perform this exercise. Often, "all" statements indicate a reconfiguration of a two-category binary into a one-category unit spectrum. All scientific studies are biased. All actions are selfish (psychological egoism). All politicians are corrupt. Everyone is racist. The transition from "whether" to "how" questions provides a clue the re-conceptualization has occurred. Rather than asking whether something is X or Not-X, we ask how much of X it is. How biased, how selfish, how corrupt, how racist.
This analytical move can cause two connected problems. The first issue pertains to the disconnect between the new and the traditional meanings of the spectrum category term. This happens because terms which typically appear in a binary context carry semantic baggage into a conversation. If I believe that everyone is biased, my use of the term "biased" will likely confuse listeners who take "biased" to mean "consequentially impartial." You ask, "Is Mario biased about this issue?" I answer, "Of course! Mario is always biased." You conclude I am negatively judging Mario's approach to the issue when perhaps I believe that, while Mario is biased, the small quantity of his bias is inconsequential. Generally speaking, the more emotionally and morally charged a term is, the greater the likelihood of semantic baggage related confusion. Often, the semantic baggage is exploited for its emotional power. If every person is racist, then the fact Joe is racist should not be alarming in the slightest. To say Joe is racist if everyone is racist is simply to say that Joe is a person. Beware of this tactic.
The second problem results from category elimination's effect on practical action. Binaries employed as heuristics for action are practically useful even if the boundary differentiating their ingredient categories is fuzzy. I can't tell you precisely when it gets dark, but I can tell you that you should take a flashlight with you when it is dark. Part of the semantic baggage of a category contains its significance for action. When we re-conceptualize a binary in the way described above, we abrogate the heuristic meaning of the retained category term. The use of the category term no longer carries any discriminatory power. If everyone is racist, then the categorization of someone as a racist loses its practical significance. Now what we do with Racist Joe depends not on his being racist but on the quantity of Joe's racism. Ultimately, the impracticality of re-conceptualizing a binary often motivates a return to its original conceptualization. Often, the original categories are bestowed new names because the old ones have become taboo (the euphemism treadmill). Instead of "retarded," we now have "mentally disabled," but the underlying conceptual distinction between retarded and not survives.
I do not oppose blowing up binaries in principle. Some binaries are worth deconstructing. What I object to is the superficial deconstruction of binaries, the exploitation of semantic baggage for self-serving purposes, and the rhetorical and behavioral confusion which ensues when a binary with heuristic meaning is eliminated but not replaced with something better. Authentic binary deconstruction is not just a word game, it requires a recognition of the purpose the binary serves and a sophisticated solution to address the practical gap created by its erasure. The principle to be everywhere is to be nowhere holds here. If there can only be quantities of light and not darkness, if there is only light everywhere, then the fact it is light tells me nothing.