Authors:

We hear things, but we can't always see them, or, even if we do see them, we're not sure that we're seeing correctly. Hence: Invisible.

Paul Auster, James M. Hutchisson (2013). “Conversations with Paul Auster”, p.211, Univ. Press of Mississippi
We hear things, but we can't always see them, or, even if we do see them, we're not sure that we're seeing correctly. Hence: Invisible.