I know, that's what I have been doing, long before reading his book, but not always closing the eyes though, just seeing without focussing. I pretend to use my right brain and not the left one and thus not thinking so hard, if there is a problem to be solved. I don't know if my two brains agree to this, but it works.
It reminds me of a joke in a Danish newspaper, maybe 70 years ago, which I cut out and have kept.
"How to make gold. Take a brick and boil it - (you see a man sitting in front of it) - but all the time while you watch it, you must never think of a hippopotamus".
That is all there is to it!