Is there any decent literature on the extent to which the fact of knowing that my shoelaces are untied is a real property of the universe? Clearly it has measurable consequences - it will result in a predictable action taking place with a high probability. Saying 'I predict that when someone will tie his shoelaces when he sees they're undone' is based not on the shoelaces being untied, nor on the photons bouncing, but on this abstract concept of them knowing. Is there a mathematical basis for stating that the universe has measurably changed in a nonrandom way once those photons' effects are analysed? I'd love to read more on this.

This was a comment from the original post, and I agree with this sentiment. There was no response, so I'm wondering if anyone can answer this question now.

Note: I don't know who the author is because I have Kibitzing on in Chrome and for some reason I cannot turn it off right now.