Look UP.. now look right.. look UP again.. look right again.. now.. look to that tennis ball.. and.. see it in your mind. Now.. look right.. and see the ball there in the air (decide).. now look UP.. (no ball).. look right again.. there it is. This modality.. very human.. is a function of our imagination. That faculty is very strechable.. to moare than you might.. know. More functions.. with and in part of our imagination.. in this book.