Ah, if you only knew what imagination really is ....!
"You say that God speaks to you - but it's only your imagination." These words were declared to Joan of Arc, at her trial, by her inquisitors.
Replied Joan of Arc: "Of course. How else does God speak to us?"
In the conventional world, we have certain notions of what imagination is. We say, "Oh, that was just your imagination" and by this, we mean: "It's not real, it has no significance, don't waste your time on it."
But when you start studying magick (which is really a form of LOA), you get a very different perspective of imagination. Will and imagination are the two fundamental tools of magick.
Imagination is how you create something on the astral plane. Will is how you supply power to that thing you've created. All things which exist in physical reality must first exist on the astral plane. All things which exist on the astral plane and are sufficiently empowered must eventually manifest in our physical reality.
Going back to the famous blue feather LOA experiment - when you visualise a blue feather, you are creating it on the astral form. The creation is instantaneous. Supply enough power, and the blue feather must pop into your physical reality. It will find its way to manifest, and it will manifest in a manner consistent with the rules of your physical reality - but it must manifest, if it has enough power.
That's how it works ....