"there is an undeniable tension between these two propositions," justice o'connor wrote in her decision. "many compilations consist of nothing but raw data—i.e. wholly factual information not accompanied by any original expression. on what basis may one claim a copyright upon such work? common sense tells us that 100 uncopyrightable facts do not magically change their status when gathered together in one place. … the key to resolving the tension lies in understanding why facts are not copyrightable: the "sine qua non" of copyright is originality."