This is indeed the ultimate sense in which History as ground and untranscendable horizon needs no particular theoretical justification: we may be sure that its alienating necessities will not forget us, however much we might prefer to ignore them.
My mind is open to a good argument (or better yet, a great story) but for now, this is what I know.
It's not that there's no truth, nor that truth lies beyond our capacity to comprehend. Rather, truth is a lot like zero - a concept we have created that is not reflected in nature.
Truth is whatever we define it to be - how could it be otherwise, since the very notion of truth is our creation?
Human rights are our creation, as is the very notion of "human", which means different things to different people. The Word of God as recorded by whichever prophet or profit motive you ascribe? Each set down in a language of human design.
Words, ritual, meaning, symbols - they are all creations of our increasingly densified noggins. All this meaning, of course, is mapped out on top of wordless drives that we interpret as validation for our beliefs, instead of vice versa.
Pluck an ardent ISIL convert and stick 'em in a room with a political ideologue and watch what happens. Their internal justifications will mimic each other; each will be spouting a truth, as emotionally true to them as they've allowed it to become, without the ends ever meeting.
The exist in silos. We exist in silos.
I know what truth is for me. That's not particularly interesting. I'm not searching for a universal truth, nor ideological domination as validation; I accept that truth lies in the eye of the beholder.
What interests me is your truth. What people choose to believe - about themselves, about others, about the world - is a window deep into the core of who they are.
To know you is to love you. To hate others is to fail in understanding oneself.
And that, folks, is... well, you know what I mean.