"I see thro' it and not with it"

In his poem, The Everlasting Gospel, Blake wrote:

This life's dim windows of the soul

Distort the heavens from pole to pole

And lead you to believe a lie

When you see with, not through, the eye.

Blake clearly believed that to accept only the material world, the world one can perceive with the senses, as real is to be deluded.