If you've just been telling without demonstrating, this is pure reliance on authority.

(Or taking a hypothetical seriously.)

An important factor is just understanding the details of how everything supposedly fits together. Even if you don't know from observation that it's the way things work in our world, there is evidence in seeing a coherent theory, as opposed to contradictory lies and confusion. Inventing a robust description of a different world is hard, more likely it's just truth about ours.