If my characters, either priest or mage, learn a spell from a book on a pedestal and then go to a teaching mage the teaching mage makes them buy the first level of the spell over again. For example my priest learned heal from a pedestal book. he then went to a teaching priest. He was offered the option to learn heal, which he already knew, not improve level with heal. if he bought that first level he could then buy more advanced levels. Interestingly enough the priest is able to use hte heal spell and it shows up in his list of spells.