Xenognosis

Knowledge that aliens, and alien minds, exist. It is, of course, a crucial aspect of first contact.
Xenologists make further distinctions between civilizational xenognosis, e.g. a planetbound early-industrial species detecting the approach of an alien starship, and personal xenognosis, when someone who knows about the existence of aliens in the abstract meets one in person for the first time. Its effects on both levels are often unpredictable, since for newly-contacted species and persons it is simply outside the context of their thought.