Ok so here's the thing. I believe an Ascian never lies... on screen and when talking with us.

Solus had to lie and lie a lot to set up the Garlean Empire i assume. Ascians lie to the beast tribes telling them that they can summon their gods and then teach them primal summoning. Elidibus is a walking lie right now because Zenos is dead (or he should be).

But for some reason these lies are never directed at us. Whenever an Ascian is with us they always seem to spill the beans somewhat. It's mostly half-truths and bait but they all seem true on some level.

That's my take anyway.