A man once told me that it is morally obligatory to lie to "the addict" (a concept I have yet to hear properly defined...But I digress.) Perhaps it's a base idea of "addicts lie, so get back at them." Or perhaps there were pretensions to high-mindedness -- after all, the man advocating deception may have believed truth is too hard-won and therefore too valuable to be squandered on those he characterized as valuing falsehood.
Do I need to spell out the obvious in that case? The nature of truth is its self-evidence. It may be hidden only deliberately, or be imperceptible to those not seeking it. It would seem hard-won only to the stupidest and most destructively delusional among us. By the way, an addict often is one because of encounters with the truth so traumatic, some narcotic palliative seemed acceptable. (To be fair, I will concede that in many cases, truths about oneself are the most traumatic.)
It's silly, really. The man espousing the aforementioned philosphy was rather full of himself and had developed some twisted idea that he was superior to those around him. His CV was a mile-long list of ERs around the country; doubtless he's a natural sadist with some sort of God complex. He probably also feels, as a corollary, that free exchanges of truth among those who desire them are a threat to whatever power over others he craves.
Forget I brought it up.