“It is true that there is no truth, and it is absolutely the case that everything is relative.”
These are the kinds of underlying premise and thought-patterns underlying the contemporary cultural milieu. Yet, there is something very strange going on behind the veil… yes, the strangeness of a madman, even.
It is often the case that evil is self-defeating. A cheater compromises his own integrity before he does the system; a murderer kills his own soul before he does his victim, and; Satan is defeated by his own act of crucifying the God-man.
What evil does for goodness, error does for truth; before undermining other truths, it defeats its own foundation, be it the statement itself or the very basis for rationality. If everything is relative, then so is that statement. If there is no truth, then such a truth-claim is also impossible.