 Tackling ethics, Carneades proceeded as he had in epistemology and constructed a framework intended to capture and do justice to the motives behind ethical theory. His framework classified not only all the views about the goal or end of life that had been held, but also all those that could be held (Cicero, Fin. 5.16–21 = L&amp;S 64EG; cf. Algra, 1997). He sets out from the assumption that practical wisdom, the knowledge we need to conduct our lives successfully, must have an object. That is, it must be knowledge of something other than itself. This immediately rules out of contention views that identify human good with knowledge without having anything to say about what it might be knowledge of apart from human good (the threat of circularity had already been noted by Plato, Republic 505bc). He further supposes that this object must be one towards which human beings have a natural impulse. There were, he maintained, three possible such objects: pleasure, freedom from pain, and the natural advantages such as health and strength. The principle of virtue corresponds to this initial choice: to be virtuous is to act with a view to obtaining one of them. There are six simple views about the goal of life, three of which identify the goal with virtue, that is, acting with a view to obtaining either pleasure, freedom from pain, or the natural advantages; and three of which identify it with actually obtaining one of these objects. Three combined views take the goal to be a combination of virtue and actually obtaining the corresponding object. There are thus nine views altogether. The Stoic position, that virtue is the only good, is the third view mentioned, namely that the goal is acting with a view to obtaining the natural advantages whether or not one obtains them.