Board Thread:Series general discussion/@comment-5088097-20170624223327/@comment-18014300-20170624232338

I actually don't recall AC1 ever establishing explicitly that Eagle Vision was only the Animus's way of representing the Assassin's observational skills.

In any case, Eagle Vision is explained in the lore as being a manifestation of the sixth sense of knowledge that the Isu supposedly possessed. I believe that the way it seems to work is that it feeds back answers to questions that the user is mentally processing. So if a user is seeking to distinguish ally from foe, Eagle Vision provides that intuitive "knowledge" for instance. If a user is seeking a passcode for a door, Eagle Vision provides that knowledge.