Weird how disorienting it can be to see something in isolation which one is used to seeing in a certain context.

The cover of the great William Gass's new novel Middle C  presented such a conundrum for me.  There's a depiction of a single piano key.

But, for a few minutes, I couldn't see it.  What is this object, I thought.

And then I saw it.  And realized it was all about context.

Like seeing a person you only know as the person in the uniform  (at insert place of employment) someplace else.