In popular parlance, "it is what it is" tends to put an end to the discussion. It is uttered, everyone nods in their collective wisdom, and moves on because, well, such is life: it is what it is. The utterance is a call to irreducible difference—"it" is not categorical, there is no shared base of knowledge, and so we will not try to speak it.
And this is, probably, often the best response. Life happens. What is there to say about it?
But to assume that something that lacks category — something that is its own category, is sui generis — cannot be spoken is to assume that language speaks in and of categories.
Language, however, gets interesting precisely when we realize that it is not solely categorical, when we realize that language is experiential. Language is as immediate and sensual as it is conceptual and categorical.
And so, for me, I find those moments when it is, indeed, what it is a great provocation to speak, to write, to deploy language. I have neither hope nor desire that my language will name it, categorize it, grasp it. No, I want my language to move with this thing, with this life.
I want the difference of this world, those moments that beguile us, that tantalize and overwhelm and confound, to spawn more and more life. I don't want them to quiet life. I want them to amplify life. And so I speak, and I write, difference.