Imagination and the Spirit World

William Blake said "Imagination is the real and eternal world of which this vegetable universe is but a faint shadow." In other words, Imagination is the Spirit World, that dreams this world into being. Imagination is often used in a 'smaller' sense almost as a subset of the ego, as fancy. But I don't think that is a valid use of the term: it betrays the real nature of the Imagination, and seems like a very modern attempt to put the non-rational under the control of the rational ego, instead of the other way round. I bring this up because a distinction is sometimes made, as though 'real' shamanism is this powerful thing that is beyond mere 'imagination'. And I don't think it is, not at all.