"I notice that when you want to stay over an extra day from college you go about it in a sure way. You never decide at first while the merits of going or staying are fairly clear in your mind. You let your imagination shinny on the side of your desires for a few hours, and then you decide. Naturally your imagination, after a little freedom, thinks up a million reasons why you should stay, so your decision when it comes isn't true. It's biassed."