From the Latin, the "negative way." It is a method of investigative teaching in which one does not define the correct way, but constantly rejects obvious mistakes. One can describe what it isn't, but not what it is. It can be a frustrating, even painful process as the student zigzags forwards from rejection to rejection. Eventually the student (if he survives!) learns to be responsible for finding his own way into the unknown. The method develops strong, curious, self-sufficient artists.