The paradox of me/not me

What we call reality is a strange business.  How can we know it?  Everything we see or perceive in any way is within us, yet if I can perceive something, I know that it is not me. I am doing the perceiving and cannot be perceived.  I am a little piece of perceivingness, like a little window.  Everything I can know about "reality", including its very existence, is within me, yet is not me.  I have no evidence that there  is anything separate from me, yet nothing I perceive can be me because I am the one doing the perceiving.  It's a paradox!

Just turn this over in your mind, please, and tell me what you experience about it.

P.S.  Perhaps I am not a "little piece" of perceivingness, but actually I am just perceivingness restricting its view?