> I would emphasize that "truth" is not a binary thing but a highly contextual and multidimensional device.
That can be taken too far and become the words of propaganda (whether or not the commenter intends it). Truth is not simple or always easy, but it's a real thing. The liar (not calling the parent a liar, but for purposes of example) says, 'the truth is complicated; we just have different opinions; look at all sides'; they say 'I lie, you lie, what's the difference?' No, there is truth, it's something to strive for, and it makes all the difference.