Cats will try and fit inside a box of any size. Look at Cosmo -- does he really think he can stuff his fuzzy frame into that box of Cheez-Its? He must, otherwise he wouldn't try ... over and over again. And he will slide across the floor, trying to wedge himself into that box until it hits the wall. He does it all the time -- like he thinks, "This time's the charm!" He must have short-term memory loss.