Theories based on observation were not always subject to [[experiment]]al test, and some errors lingered on for centuries. The best known was Aristotle's theory of [[falling objects]], which despite its went essentially unchallenged until the [[Renaissance]]. | Theories based on observation were not always subject to [[experiment]]al test, and some errors lingered on for centuries. The best known was Aristotle's theory of [[falling objects]], which despite its went essentially unchallenged until the [[Renaissance]]. |