What does Bigger mean when he says, "Half the time I feel like I'm on the outside of the world peeping in through a knot-hole in the fence"?

When Bigger says, 'Half the time I feel like I'm on the outside of the world peeping in through a knot-hole in the fence' he means that, he feels as if he is not a part of this world.

Explanation:

Bigger Thomas is a central character from the novel 'Native Son' which is authored by Richard Wright. The story revolves around a the protagonist Bigger who is poor and a black man.

In the novel we come across a phase when Bigger says, 'Half the time I feel like I'm on the outside of the world peeping in through a knot-hole in the fence.' By this he means that despite being a part of the world, he feels detached. He doesn't consider himself as a part of it, he feels that this world is beyond his understanding.